What is DNS (Domain Name System)?
Turkish: DNS
DNS maps readable domain names to IP addresses so browsers, email servers, and APIs can reach the right destination without hard-coded numbers.
What is DNS?
DNS (Domain Name System) is the translation layer between human-readable domain names and the IP addresses used by machines. When someone enters bdijital.com in a browser, DNS records decide which server receives that request; when email is sent, DNS also helps locate the right mail servers.
How Does DNS Work?
A device first checks its local cache, then usually asks a recursive resolver operated by an ISP, office network, or public DNS provider. If the resolver does not already know the answer, it queries the root DNS, the TLD DNS, and finally the authoritative DNS server for that domain. The answer is cached for a TTL period.
This distributed design avoids a single central lookup service for every internet request. The tradeoff is that a wrong record, stale cache, or rushed migration can send a website, API, or email flow to the wrong place.
Common DNS Uses
- A and AAAA records: Point a domain to IPv4 or IPv6 addresses
- CNAME: Points one hostname to another hostname
- MX: Defines where email for the domain should be delivered
- TXT: Supports SPF, DKIM, domain verification, and other text-based checks
- NS: Shows which authoritative name servers manage the domain
Business Use
DNS is part of every website launch, CDN setup, email authentication, subdomain structure, and third-party service integration. A payment provider, email platform, or Cloudflare setup often starts with a TXT, CNAME, or MX record.
During a domain migration, lowering TTL values in advance, scheduling changes carefully, and keeping old and new services available for a transition window reduces outage risk.
Related Terms
Anycast advertises the same IP address from multiple locations and uses BGP routing to send traffic to the nearest or best network point.
CloudflareCloudflare is a global internet platform providing DNS, CDN, security, performance, and edge compute services from one network.
CNAME (Canonical Name Record)A CNAME record maps one domain name to another as an alias, commonly used for subdomains, SaaS apps, and CDN endpoints.
DNS PropagationDNS propagation is the period during which a changed DNS record spreads through recursive resolvers and caches around the world.
DNS RecordA DNS record is an instruction that tells a domain where to send web traffic, email, verification checks, or other internet requests.
Domain NameA domain name is the memorable internet address people use to reach a website, application, API, or email service.
IP AddressAn IP address is a numeric label used to identify devices on a network and route data packets to the correct destination.
TCP/IPTCP/IP is the protocol suite that defines addressing, packet routing, and reliable data transfer across internet-connected networks.
TTL (Time to Live)TTL defines how long DNS records or cache entries are considered valid before they must be requested or generated again.