SEO · Definition
301 redirect
An HTTP status indicating that a resource has moved permanently to another URL.
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Domain nameDNSWeb hosting
A human-readable name in the Domain Name System that identifies a place in its hierarchical namespace.
DNSThe Domain Name System is a distributed system that answers queries about names using typed records.
Web hostingA service that makes website files or an application available to people over a network.
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All terms200
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SEO · Definition
302 redirect
An HTTP status indicating a temporary redirection to another URL.
Understand the termSEO · Definition
404 error
An HTTP status indicating that the server cannot find a current representation of the requested resource.
Understand the termDNS · Definition
A record
A DNS record that associates a name with an IPv4 address.
Understand the termDNS · Definition
AAAA record
A DNS record that associates a name with an IPv6 address.
Understand the termSite building · Definition
Accessibility
The practice of making products usable by people with a broad range of abilities and assistive technologies.
Understand the termSite building · Definition
Alt text
A text alternative that communicates an image's information or function when the image is not perceived.
Understand the termSEO · Definition
Anchor text
The readable text of a hyperlink that communicates something about its destination.
Understand the termDomains · Definition
Apex domain
The domain at the top of a particular DNS zone, also called the zone apex.
Understand the termSite building · Definition
API
An application programming interface defines how software can request data or behavior from another component.
Understand the termHosting · Definition
Application server
Software that runs application logic and generates responses using code, data, or other services.
Understand the termSecurity · Definition
Authentication
The process of checking that a person or system is who or what it claims to be.
Understand the termDNS · Definition
Authoritative nameserver
A nameserver that answers from the DNS zone data it is responsible for serving.
Understand the termSecurity · Definition
Authorization
The decision about which actions or resources an identity is allowed to access.
Understand the termDomains · Definition
Authorization code
A credential used in applicable registrar transfer workflows to authorize a domain transfer.
Understand the termEcommerce · Definition
Backorder
An order accepted for an item that is currently unavailable for immediate fulfillment.
Understand the termSecurity · Definition
Backup
A recoverable copy of data or system state kept to support restoration after loss or unwanted change.
Understand the termHosting · Definition
Bandwidth
The data-carrying capacity of a network connection; hosting plans also use the word for an allowance of transferred data.
Understand the termWordPress · Definition
Block editor
The WordPress editing interface that represents content as individual blocks with controls and structure.
Understand the termWordPress · Definition
Block pattern
A predefined arrangement of WordPress blocks that can be inserted as a starting point for content.
Understand the termWordPress · Definition
Block theme
A WordPress theme built around blocks for editing site templates and other design areas.
Understand the termSite building · Definition
Breadcrumb
A compact trail of links showing a page's place within a site hierarchy.
Understand the termPerformance · Definition
Browser cache
A browser's local storage of reusable web responses, governed by caching rules and validation behavior.
Understand the termDNS · Definition
CAA record
A DNS Certification Authority Authorization record states which certificate authorities may issue certificates for a domain.
Understand the termPerformance · Definition
Cache
A store of reusable results or data that can reduce repeated retrieval or computation.
Understand the termSEO · Definition
Canonical URL
The preferred representative URL selected or indicated for a set of duplicate or closely similar pages.
Understand the termPerformance · Definition
CDN
A content delivery network distributes delivery through geographically spread infrastructure that can cache or proxy content.
Understand the termSecurity · Definition
Certificate authority
An organization or system that issues digital certificates within a trust framework.
Understand the termEcommerce · Definition
Checkout
The workflow in which a shopper supplies required details, reviews the order, and submits a purchase.
Understand the termWordPress · Definition
Child theme
A WordPress theme that inherits from another theme and provides its own supported overrides or additions.
Understand the termHosting · Definition
Cloud hosting
Hosting delivered using pooled, provisioned computing infrastructure instead of a single fixed hosting arrangement.
Understand the termDNS · Definition
CNAME record
A DNS record that makes one name an alias of another canonical name.
Understand the termPerformance · Definition
Compression
The reduction of data size using an encoding that a recipient can decode.
Understand the termHosting · Definition
Container
An isolated process environment that packages an application's software and dependencies while sharing the host operating-system kernel.
Understand the termSite building · Definition
Content management system
Software for organizing, editing, and publishing content through an application interface.
Understand the termSite building · Definition
Cookie
A small item of data a browser stores and sends with matching requests according to its attributes and browser rules.
Understand the termPerformance · Definition
Core Web Vitals
A set of user-experience metrics covering loading, interaction responsiveness, and visual stability, currently LCP, INP, and CLS.
Understand the termEcommerce · Definition
Coupon
A configured promotion that applies a discount or benefit when its eligibility rules are satisfied.
Understand the termHosting · Definition
CPU
The central processing unit executes instructions used by operating systems and applications.
Understand the termSEO · Definition
Crawling
The discovery and fetching of pages or resources by an automated crawler.
Understand the termSite building · Definition
CSS
Cascading Style Sheets define how web content is presented, including layout, typography, spacing, and visual states.
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Cumulative Layout Shift
CLS measures unexpected visual movement of page elements using a session-window method.
Understand the termHosting · Definition
Data transfer
The amount of data moved across a connection during a stated period or operation.
Understand the termHosting · Definition
Database
An organized collection of data managed so applications can store, query, and update information.
Understand the termHosting · Definition
Dedicated server
A physical server allocated to one customer rather than a shared customer environment.
Understand the termSite building · Definition
Deployment
The process of placing a chosen software or content version into an environment where it can run or be served.
Understand the termEmail · Definition
DKIM
DomainKeys Identified Mail attaches a domain-associated cryptographic signature that receiving systems can verify using DNS.
Understand the termEmail · Definition
DMARC
An email authentication policy and reporting mechanism that relates SPF or DKIM authentication to the visible From domain through alignment.
Understand the termDNS · Definition
DNS
The Domain Name System is a distributed system that answers queries about names using typed records.
Understand the termDNS · Definition
DNS cache
A temporary store of DNS answers kept to avoid repeating the same lookup immediately.
Understand the termDNS · Definition
DNS delegation
The assignment of authority for a child zone to nameservers, recorded in its parent zone.
Understand the termDNS · Definition
DNS propagation
An informal name for the period in which changed DNS data becomes visible through different servers and caches.
Understand the termDNS · Definition
DNS record
A typed piece of information associated with a name in a DNS zone.
Understand the termDNS · Definition
DNS TTL
Time to live specifies how long a DNS answer may remain in a cache before it needs refreshing.
Understand the termDNS · Definition
DNS zone
An administratively managed portion of the DNS namespace for which a server provides authoritative data.
Understand the termDNS · Definition
DNSSEC
A set of DNS extensions that lets validating resolvers check the authenticity and integrity of signed DNS data.
Understand the termDomains · Definition
Domain expiration
The point at which a domain's current registration term ends without a completed renewal.
Understand the termDomains · Definition
Domain lock
A status or setting that restricts specified domain changes, often including registrar transfer.
Understand the termDomains · Definition
Domain name
A human-readable name in the Domain Name System that identifies a place in its hierarchical namespace.
Understand the termDomains · Definition
Domain privacy
A registration service or data-publication arrangement that limits which personal contact details appear publicly.
Understand the termDomains · Definition
Domain renewal
The extension of a domain registration for an additional permitted term.
Understand the termDomains · Definition
Domain transfer
A change of sponsoring registrar for a domain registration.
Understand the termSEO · Definition
Duplicate content
Content that is identical or substantially similar at more than one URL.
Understand the termSite building · Definition
Dynamic website
A website that can generate responses using application logic and data at request time.
Understand the termEcommerce · Definition
Ecommerce
The buying and selling of products or services through electronic systems, including online storefronts.
Understand the termEmail · Definition
Email alias
An alternate email address that delivers messages to another address or mailbox according to the mail service's configuration.
Understand the termEmail · Definition
Email bounce
A delivery failure notification generated when a message cannot be delivered as expected.
Understand the termEmail · Definition
Email client
Software used to compose, send, receive, and organize email through configured accounts.
Understand the termEmail · Definition
Email deliverability
The practical ability of legitimate mail to reach its intended destination, including acceptance and placement decisions by receiving systems.
Understand the termEmail · Definition
Email forwarding
A mail-routing arrangement that passes received messages to another email address.
Understand the termEmail · Definition
Email header
A structured field in a message carrying information such as its sender, recipient, subject, or transport history.
Understand the termEmail · Definition
Email spoofing
The use of falsified sender information to make an email appear to originate from someone else.
Understand the termSecurity · Definition
Encryption
A transformation that makes readable data unintelligible without the appropriate cryptographic key.
Understand the termPerformance · Definition
Field data
Performance measurements collected from real visits in actual user environments.
Understand the termSecurity · Definition
Firewall
A control that permits or blocks network traffic according to configured rules.
Understand the termPerformance · Definition
First Contentful Paint
FCP marks when a browser first renders qualifying content from the page.
Understand the termEcommerce · Definition
Fulfillment
The operational process of preparing and delivering the goods or service promised by an order.
Understand the termSecurity · Definition
Hashing
The calculation of a fixed-size digest from input data using a hash function.
Understand the termSEO · Definition
hreflang
A link annotation identifying alternate versions of a page for specified languages or regions.
Understand the termSite building · Definition
HTML
HyperText Markup Language expresses the structure and meaning of web content with elements and attributes.
Understand the termSite building · Definition
HTTP
Hypertext Transfer Protocol defines how clients and servers exchange web requests and responses.
Understand the termSecurity · Definition
HTTPS
HTTP communicated over an encrypted TLS connection that protects transport between participating endpoints.
Understand the termEmail · Definition
IMAP
Internet Message Access Protocol lets clients access and manage messages held on a mail server.
Understand the termSecurity · Definition
Incident response
A coordinated process for assessing, containing, investigating, and recovering from a suspected security incident.
Understand the termSEO · Definition
Indexing
The processing and potential storage of page information in a search engine's searchable index.
Understand the termPerformance · Definition
Interaction to Next Paint
INP assesses page responsiveness by examining the latency of qualifying interactions over a visit.
Understand the termSEO · Definition
Internal link
A hyperlink connecting one page to another within the same website.
Understand the termDomains · Definition
Internationalized domain name
A domain name containing characters represented through the internationalized domain-name system beyond basic ASCII letters, digits, and hyphens.
Understand the termEcommerce · Definition
Inventory
The quantity and state of items a business tracks as available, reserved, or otherwise held for sale.
Understand the termSite building · Definition
JavaScript
A programming language widely used to add behavior to web pages and run application logic in other environments.
Understand the termPerformance · Definition
Lab data
Measurements collected in a controlled or simulated test environment.
Understand the termPerformance · Definition
Largest Contentful Paint
LCP reports when the largest eligible visible content element in the initial viewport is rendered.
Understand the termPerformance · Definition
Latency
The delay between initiating an operation and receiving a response or result.
Understand the termPerformance · Definition
Lazy loading
The deferral of nonessential resource loading until the resource is needed or near use.
Understand the termSecurity · Definition
Least privilege
The principle of granting only the access needed for a person's or system's current task.
Understand the termHosting · Definition
Load balancer
A component that distributes incoming work among multiple backend servers or instances.
Understand the termEmail · Definition
Mailbox
A storage destination for messages associated with an email account.
Understand the termEmail · Definition
Mailing list
A managed group of email recipients served through a list address or sending system.
Understand the termSecurity · Definition
Malware
Software intentionally designed to compromise, disrupt, exploit, or otherwise misuse systems or data.
Understand the termHosting · Definition
Managed hosting
A hosting arrangement in which a provider takes responsibility for specified operational tasks.
Understand the termHosting · Definition
Memory
Working space used by running software to hold data it needs to access quickly.
Understand the termEmail · Definition
Message-ID
A message header field intended to identify a particular version of an email message.
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Meta description
An HTML metadata field offering a summary of a page's content.
Understand the termPerformance · Definition
Minification
The removal of unnecessary characters or other safe simplifications from source assets to reduce their size.
Understand the termPerformance · Definition
Monitoring
The ongoing collection and evaluation of signals used to understand a system's condition and detect problems.
Understand the termSecurity · Definition
Multi-factor authentication
Authentication requiring evidence from more than one category of factor, such as something known and something possessed.
Understand the termDNS · Definition
MX record
A DNS record that identifies a mail exchanger for a domain and its preference value.
Understand the termDNS · Definition
Nameserver
A server that answers DNS questions, either using authoritative data or by resolving and caching answers.
Understand the termSEO · Definition
noindex
A robots directive asking supporting search engines not to include a page in search results.
Understand the termDNS · Definition
NS record
A DNS record that identifies a nameserver responsible for a zone.
Understand the termHosting · Definition
Object storage
A storage model that keeps data as objects with an identifier and metadata rather than a traditional mounted file hierarchy.
Understand the termEcommerce · Definition
Order confirmation
A page or message acknowledging an order and presenting its recorded details.
Understand the termEcommerce · Definition
Order status
A label representing an order's current stage in a store's processing workflow.
Understand the termSEO · Definition
Organic search
Visits or visibility arising from unpaid search results rather than paid search advertisements.
Understand the termEcommerce · Definition
Payment authorization
A payment-processing step that checks and, for supported payment flows, reserves an amount for a potential later capture.
Understand the termEcommerce · Definition
Payment capture
The step that requests collection of a previously authorized payment amount in a supported payment flow.
Understand the termEcommerce · Definition
Payment gateway
A service or integration that connects checkout to payment processing and communicates payment results.
Understand the termPerformance · Definition
Performance budget
A deliberately chosen limit or target used to guide and review a site's performance-related decisions.
Understand the termSecurity · Definition
Phishing
A deceptive attempt to make someone reveal information or perform an action by impersonating a trusted party.
Understand the termWordPress · Definition
Plugin conflict
An incompatibility in which a plugin interacts badly with another extension, theme, core version, or environment.
Understand the termEmail · Definition
POP3
Post Office Protocol version 3 is a protocol for retrieving messages from a server mailbox.
Understand the termEcommerce · Definition
Product catalog
The organized set of product information a store uses to present and manage its offering.
Understand the termEcommerce · Definition
Product variant
A specific purchasable version of a product distinguished by attributes such as size or color.
Understand the termDNS · Definition
PTR record
A DNS record that points a name to another name, commonly used in reverse DNS lookup.
Understand the termDomains · Definition
Public suffix
A suffix under which users can register names, including some multi-label and platform-specific boundaries.
Understand the termDomains · Definition
Punycode
An encoding used to represent supported internationalized domain labels with ASCII characters.
Understand the termDomains · Definition
RDAP
The Registration Data Access Protocol provides structured access to internet registration data.
Understand the termSecurity · Definition
Recovery code
A pre-issued secret that can restore account access when a normal authentication method is unavailable.
Understand the termDNS · Definition
Recursive resolver
A DNS service that finds an answer for a client by querying other servers as needed and usually caching results.
Understand the termDomains · Definition
Redemption period
A domain lifecycle stage in which certain deleted registrations may be restorable through the registrar under applicable rules.
Understand the termSEO · Definition
Redirect
A response or mechanism that sends a user agent from one URL to another.
Understand the termDomains · Definition
Registrant
The person or organization holding the registration rights for a domain under its registration agreement.
Understand the termDomains · Definition
Registrar
An organization through which a registrant registers and manages a domain under the relevant registry's rules.
Understand the termDomains · Definition
Registry
The organization responsible for operating the database and registration system for a domain namespace.
Understand the termPerformance · Definition
Render blocking
The condition in which a resource or task delays the browser from rendering content.
Understand the termHosting · Definition
Resource limit
A configured boundary on how much of a system resource an account or process can consume.
Understand the termSite building · Definition
Responsive design
An approach that adapts content presentation to available space and device characteristics.
Understand the termPerformance · Definition
Responsive images
Image markup that lets a browser select suitable sources for layout size, resolution, or art direction.
Understand the termSecurity · Definition
Restore point
A particular saved state or time to which a system or dataset can be recovered using available backups.
Understand the termEmail · Definition
Reverse DNS
A lookup that maps an IP address to a name using the reverse DNS namespace, commonly through PTR records.
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robots.txt
A file at a site's root that gives compliant crawlers rules about which URLs they may request.
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Scalability
The ability of a system to accommodate changing workload by adjusting resources or architecture.
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Search Console
Google's tool for viewing a verified property's search performance, indexing information, and related diagnostics.
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Search intent
The task or information need a person is trying to satisfy through a query.
Understand the termDomains · Definition
Second-level domain
A domain label immediately beneath a top-level domain in the DNS hierarchy.
Understand the termSecurity · Definition
Security update
A software release or patch intended to address identified security weaknesses.
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Service-level agreement
An agreement that defines service commitments, their measurement, exclusions, and any stated remedies.
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Session
A way an application associates a sequence of interactions with an ongoing user or client context.
Understand the termHosting · Definition
Shared hosting
Hosting in which multiple customer accounts use resources on the same server environment.
Understand the termEcommerce · Definition
Shipping zone
A geographic area a store uses to determine which configured shipping methods apply.
Understand the termEcommerce · Definition
Shopping cart
A temporary collection of products and quantities a shopper is considering buying.
Understand the termEcommerce · Definition
Simple product
A WooCommerce product type for an individual product without selectable purchasing variations.
Understand the termWordPress · Definition
Site Editor
The WordPress interface for editing site-level templates, styles, and other supported design elements with a block theme.
Understand the termEcommerce · Definition
SKU
A stock keeping unit is an identifier a business assigns to distinguish inventory items.
Understand the termSite building · Definition
Slug
A human-readable identifier commonly used as the final meaningful segment of a content URL.
Understand the termEmail · Definition
SMTP
Simple Mail Transfer Protocol is used to submit and transfer email between systems.
Understand the termEmail · Definition
SMTP status code
A server reply code describing the result of a step in an SMTP exchange.
Understand the termDNS · Definition
SOA record
A Start of Authority record provides administrative and timing information for a DNS zone.
Understand the termEmail · Definition
SPF
Sender Policy Framework lets a domain publish which senders are authorized for the envelope-from or HELO identity used in mail transport.
Understand the termSite building · Definition
Staging environment
A separate environment used to review and test changes before they reach the live site.
Understand the termSite building · Definition
Static website
A website primarily served from prebuilt files rather than generating each page's HTML on demand.
Understand the termEcommerce · Definition
Stock status
A label describing whether an item is currently offered as in stock, out of stock, or available under another stock policy.
Understand the termSEO · Definition
Structured data
Machine-readable markup using a defined vocabulary to describe entities or content on a page.
Understand the termDomains · Definition
Subdomain
A domain located below another domain in the DNS hierarchy.
Understand the termWordPress · Definition
Synced pattern
A WordPress pattern whose content and structure can be reused with changes synchronized across its instances.
Understand the termWordPress · Definition
Template hierarchy
The ordered selection rules WordPress uses to choose a template for a requested view.
Understand the termPerformance · Definition
Time to First Byte
TTFB measures the time from a request's start until the first byte of its response arrives.
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Title element
The HTML element that names a document for browsers and other consumers, including search systems.
Understand the termSecurity · Definition
TLS
Transport Layer Security is a protocol that provides encryption, integrity protection, and authentication for network connections.
Understand the termSecurity · Definition
TLS certificate
A signed digital document that associates an identity, such as domain names, with a public key used in TLS authentication.
Understand the termDomains · Definition
Top-level domain
The highest named level of the public domain hierarchy, immediately beneath the root.
Understand the termEmail · Definition
Transactional email
A message triggered by a specific action or service event, such as an account request or order update.
Understand the termDNS · Definition
TXT record
A DNS record containing text strings used by services for information or verification.
Understand the termPerformance · Definition
Uptime
The time or proportion of time a monitored system is considered available under a stated definition.
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URL
A Uniform Resource Locator identifies a resource using components such as a scheme, host, path, and optional query or fragment.
Understand the termEcommerce · Definition
Variable product
A WooCommerce product type that offers variations with attributes and potentially distinct prices, stock, or images.
Understand the termSite building · Definition
Viewport
The region through which a user views a web document, with layout and visual viewport concepts on mobile devices.
Understand the termHosting · Definition
Virtual machine
A software-defined computer that runs a guest operating system using resources supplied by a host.
Understand the termHosting · Definition
VPS
A virtual private server is a virtual machine supplied with an operating system and an allocation of compute resources.
Understand the termSecurity · Definition
Vulnerability
A weakness that can be exploited to violate a system's intended security properties.
Understand the termSecurity · Definition
Web application firewall
A control that inspects web requests and responses against rules intended to identify or block unwanted application traffic.
Understand the termHosting · Definition
Web hosting
A service that makes website files or an application available to people over a network.
Understand the termHosting · Definition
Web server
Software that receives web requests and sends responses, or the computer running that software.
Understand the termEcommerce · Definition
Webhook
An HTTP request sent by one system to notify another system of an event.
Understand the termEmail · Definition
Webmail
An email application accessed through a web browser.
Understand the termSite building · Definition
Website navigation
The controls and links that help people understand a site's organization and move between content or tasks.
Understand the termDomains · Definition
WHOIS
A traditional protocol and lookup system for accessing domain registration information.
Understand the termWordPress · Definition
WordPress
An open-source content management system used to create and manage websites through software installed in a hosting environment.
Understand the termWordPress · Definition
WordPress block
A unit of content or functionality used in WordPress's block-based editing system.
Understand the termWordPress · Definition
WordPress core
The main WordPress software maintained by the WordPress project, separate from themes, plugins, and site content.
Understand the termWordPress · Definition
WordPress database
The database WordPress uses to store structured site information such as posts, users, settings, and relationships.
Understand the termWordPress · Definition
WordPress permalink
The lasting URL structure WordPress uses for individual content and other public views.
Understand the termWordPress · Definition
WordPress plugin
An extension that adds or changes WordPress functionality without modifying the core software directly.
Understand the termWordPress · Definition
WordPress role
A named collection of capabilities assigned to a user account.
Understand the termWordPress · Definition
WordPress template
A layout definition WordPress uses to render a particular type of page or view.
Understand the termWordPress · Definition
WordPress theme
A collection of templates and styling that controls a WordPress site's presentation and, depending on its type, editing features.
Understand the termWordPress · Definition
WordPress update
A replacement of WordPress core, a theme, or a plugin with a newer released version.
Understand the termWordPress · Definition
WordPress user
An account recognized by a WordPress installation, with a role and profile information.
Understand the termWordPress · Definition
WP-Cron
WordPress's system for scheduling tasks, normally checked during page loads unless an alternative trigger is configured.
Understand the termSEO · Definition
XML sitemap
A machine-readable file listing URLs a site wants search engines to discover, optionally with supported metadata.
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Hosting
Understand the infrastructure and responsibilities behind a published website.
20 definitions02Domains
Understand registration, ownership, renewal, and the structure of a domain name.
20 definitions03DNS
Connect names to services and make sense of records, authority, and caching.
20 definitions04Understand mailboxes, message transport, authentication, and delivery evidence.
20 definitions05WordPress
Understand the content, editing, extension, and maintenance concepts in WordPress.
20 definitions06Ecommerce
Understand the catalog, checkout, payment, and fulfillment language of an online store.
20 definitions07Security
Understand identity, access, transport protection, and recovery concepts.
20 definitions08Performance
Understand loading, responsiveness, caching, measurement, and operational signals.
20 definitions09SEO
Understand how pages are discovered, indexed, represented, and connected in search.
20 definitions10Site building
Understand the structure, behavior, navigation, and publishing of a website.
20 definitionsHow do I choose between a glossary definition and a practical guide?
Use a glossary entry to understand a term through its definition, example, caution, and related concepts. Use the learning center when you need a deliverable, a sequence of steps, and acceptance checks for a website task.
Where can I untangle hosting, domain, DNS, and email terminology?
Browse these topics according to the service you are trying to understand:
- Hosting: Understand the infrastructure and responsibilities behind a published website.
- Domains: Understand registration, ownership, renewal, and the structure of a domain name.
- DNS: Connect names to services and make sense of records, authority, and caching.
- Email: Understand mailboxes, message transport, authentication, and delivery evidence.
How can I find a term and keep exploring its context?
Search by a term or phrase and use the topic filter to narrow the collection. Clear the filters to return to the full directory. Each entry links to related definitions and practical guides; the site-building topic is a starting point for website structure, navigation, and publishing.