What is an HTTP Request? Methods, headers, and code

An HTTP request is a structured message sent from a client to a server to request resources or actions, integral to web interactions like loading pages or API calls. It operates at the application layer of the TCP/IP stack and consists of a request line, headers, and an optional body, allowing for extensibility without altering core protocol rules. HTTP's stateless nature enables horizontal scaling, while headers and methods like GET and POST dictate processing and caching behaviors. HTTP/2 and HTTP/3 introduce performance enhancements such as multiplexing and reduced latency by using QUIC instead of TCP. Understanding the journey of an HTTP request—from DNS lookup to TLS handshake and finally server response—enables identification and resolution of network inefficiencies, ensuring optimal application performance.