Web infrastructure glossary
Clear definitions for domain names, DNS, web hosting, servers, HTTPS, email, networking, and web technology.
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Eight foundational terms that connect the rest of the glossary.
- Content delivery network (CDN)A content delivery network (CDN) serves cached or proxied content from a distributed network of locations.
- Domain nameA domain name is a human-readable name used to identify an Internet destination, such as example.com.
- Domain Name System (DNS)The Domain Name System (DNS) is the distributed system that publishes and resolves names used by Internet services.
- HTTPSHTTPS is HTTP exchanged over a connection protected by Transport Layer Security (TLS).
- IP address (IP)An IP address is a numerical identifier used to address a network interface with the Internet Protocol.
- Shared hostingShared hosting is a hosting model where multiple customer websites use a provider-managed server platform.
- Simple Mail Transfer Protocol (SMTP)Simple Mail Transfer Protocol (SMTP) is the standard protocol used to submit and relay email messages.
- SSL certificateAn SSL certificate is the common name for a digital certificate used to authenticate a hostname during TLS.
All glossary terms
A
- A recordDomains & DNSAn A record is a DNS record that maps a hostname to an IPv4 address.
- AAAA recordDomains & DNSAn AAAA record is a DNS record that maps a hostname to an IPv6 address.
- Application programming interface (API)Web & DevelopmentAn application programming interface (API) is a defined way for software systems to exchange requests and data.
- Authoritative nameserverDomains & DNSAn authoritative nameserver is a DNS server that publishes the source records for a DNS zone.
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- CachePerformance & CDNA cache stores a reusable copy of data so later requests can be served more quickly.
- Certificate authority (CA)Security & EncryptionA certificate authority (CA) is an organization trusted to issue and sign digital certificates.
- Certificate signing request (CSR)Security & EncryptionA certificate signing request (CSR) is a signed request containing a public key and identifying information for a new certificate.
- CipherSecurity & EncryptionA cipher is an algorithm that transforms readable data into protected data and back when the correct key is available.
- CNAME record (CNAME)Domains & DNSA CNAME record is a DNS record that makes one hostname an alias of another hostname.
- Content delivery network (CDN)Performance & CDNA content delivery network (CDN) serves cached or proxied content from a distributed network of locations.
- Content management system (CMS)Web & DevelopmentA content management system (CMS) is software used to create, organize, and publish website content.
- Control panelHosting & ServersA hosting control panel is a web interface for managing common website, domain, email, database, and account tasks.
D
- DatabaseWeb & DevelopmentA database is an organized collection of data managed so applications can store, retrieve, and update information.
- Dedicated serverHosting & ServersA dedicated server is a physical server assigned to one customer or workload rather than shared as separate virtual servers.
- Distributed denial-of-service attack (DDoS)Security & EncryptionA distributed denial-of-service (DDoS) attack floods a target with traffic from many sources to make it slow or unreachable.
- DNS propagationDomains & DNSDNS propagation is the transition period after a DNS change, while cached answers expire unevenly across resolvers.
- DNS recordDomains & DNSA DNS record is a structured entry that publishes information about a name in the Domain Name System.
- Domain nameDomains & DNSA domain name is a human-readable name used to identify an Internet destination, such as example.com.
- Domain Name System (DNS)Domains & DNSThe Domain Name System (DNS) is the distributed system that publishes and resolves names used by Internet services.
- Domain registrarDomains & DNSA domain registrar is a company authorized to register and manage domain names for customers.
- Domain registryDomains & DNSA domain registry is the organization that operates a top-level domain and maintains its master database of registrations.
- Domain transferDomains & DNSA domain transfer moves a domain name's sponsorship from one registrar to another.
- Domain-based Message Authentication, Reporting, and Conformance (DMARC)Email & CommunicationDMARC is an email-authentication policy that uses SPF and DKIM results plus domain alignment to guide message handling.
- DomainKeys Identified Mail (DKIM)Email & CommunicationDomainKeys Identified Mail (DKIM) lets a sending domain add a cryptographic signature to an email message.
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- HTTP redirectWeb & DevelopmentAn HTTP redirect is a server response that tells the client to fetch a different URL instead.
- HTTP status codeWeb & DevelopmentAn HTTP status code is a three-digit value that summarizes the result of an HTTP request.
- HTTP Strict Transport Security (HSTS)Security & EncryptionHTTP Strict Transport Security (HSTS) is a web security policy that tells browsers to use HTTPS for a host.
- HTTPSSecurity & EncryptionHTTPS is HTTP exchanged over a connection protected by Transport Layer Security (TLS).
- Hypertext Markup Language (HTML)Web & DevelopmentHypertext Markup Language (HTML) is the standard markup language used to structure content on web pages.
- Hypertext Transfer Protocol (HTTP)Web & DevelopmentHypertext Transfer Protocol (HTTP) defines how clients and servers exchange requests and responses on the web.
I
- Internet Message Access Protocol (IMAP)Email & CommunicationInternet Message Access Protocol (IMAP) lets an email client access and manage messages stored on a mail server.
- IP address (IP)Networking & IPAn IP address is a numerical identifier used to address a network interface with the Internet Protocol.
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- LatencyPerformance & CDNLatency is the delay between an action or request and the corresponding response or data transfer.
- Let's EncryptSecurity & EncryptionLet's Encrypt is a nonprofit certificate authority that issues publicly trusted TLS certificates through an automated process.
- Load balancerPerformance & CDNA load balancer distributes incoming requests or connections across multiple service instances.
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- Secure Shell (SSH)Security & EncryptionSecure Shell (SSH) is a protocol for authenticated, encrypted access to remote systems and services.
- Sender Policy Framework (SPF)Email & CommunicationSender Policy Framework (SPF) lets a domain publish which sending systems are authorized for its email envelope domain.
- ServerHosting & ServersA server is software or a computer that provides data or services to other systems called clients.
- Shared hostingHosting & ServersShared hosting is a hosting model where multiple customer websites use a provider-managed server platform.
- Simple Mail Transfer Protocol (SMTP)Email & CommunicationSimple Mail Transfer Protocol (SMTP) is the standard protocol used to submit and relay email messages.
- SSH File Transfer Protocol (SFTP)Web & DevelopmentSSH File Transfer Protocol (SFTP) is a file transfer and management protocol that runs inside an SSH connection.
- SSL certificateSecurity & EncryptionAn SSL certificate is the common name for a digital certificate used to authenticate a hostname during TLS.
- SubdomainDomains & DNSA subdomain is a domain name that sits below another domain in the DNS hierarchy.
T
- Time to live (TTL)Domains & DNSIn DNS, time to live (TTL) is the number of seconds a record may be cached before it should be refreshed.
- Top-level domain (TLD)Domains & DNSA top-level domain (TLD) is the label at the highest visible level of a domain name, such as .com or .org.
- Transport Layer Security (TLS)Security & EncryptionTransport Layer Security (TLS) is a protocol that protects network communication with encryption, integrity checks, and authentication.
- TXT recordDomains & DNSA TXT record is a DNS record that publishes text at a name, most often for verification and email authentication.
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- Virtual machine (VM)Hosting & ServersA virtual machine (VM) is an isolated computing environment that emulates a computer on shared physical hardware.
- Virtual private server (VPS)Hosting & ServersA virtual private server (VPS) is a virtual machine sold as an independently administered server environment.
W
- Web hostingHosting & ServersWeb hosting is a service that provides the computing, storage, network access, and software environment needed to publish a website.
- WHOISDomains & DNSWHOIS is a long-standing query system for looking up registration data associated with Internet resources such as domain names.
- WordPressWeb & DevelopmentWordPress is open-source content management software used to create and manage websites.