Web & Networking

HTTP Status Codes (2xx / 4xx / 5xx)

Three-digit response codes returned by HTTP servers. 2xx = success, 3xx = redirect, 4xx = client error (bad request), 5xx = server error. Monitoring tools alert on 4xx/5xx codes.

Sources

IETF — RFC 9110 §15 — Status Codes
MDN Web Docs — HTTP response status codes

Related terms

Timeout

The maximum time a client waits for a response before giving up.

DNS (Domain Name System)

The internet's address book — translates human-readable domain names like foursight.cloud into IP addresses…

A Record

A DNS record that maps a hostname to an IPv4 address (e.g.

AAAA Record

Maps a hostname to an IPv6 address.

CNAME Record

An alias DNS record that points one hostname to another (e.g.

MX Record

Identifies the mail servers responsible for accepting email for a domain.

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