The Hypertext Transfer Protocol (HTTP) is the foundation of data communication for the World Wide Web. It defines how messages are formatted and transmitted, and how web servers and browsers respond to various commands. HTTP operates over TCP/IP, typically using port 80 for unencrypted connections and port 443 for encrypted connections (HTTPS). It enables clients (such as web browsers) to request resources (such as HTML documents, images, or scripts) from web servers and receive responses that include the requested content along with status information.
HTTP protocol works step by step through a series of interactions between a client (e.g., a web browser) and a server (e.g., a web server). The process begins when the client sends an HTTP request message to the server. This request specifies the resource (e.g., a webpage URL) that the client wants to access and may include additional headers that provide information about the client or request parameters. The server then processes the request, retrieves the requested resource, and constructs an HTTP response message containing the resource data along with metadata like status codes (e.g., 200 OK or 404 Not Found).
An HTTP website operates by serving content and resources to clients (web browsers) that connect to it using HTTP or HTTPS protocols. When a user enters a website’s URL into a browser, the browser sends an HTTP request to the web server hosting the site. The server responds by sending back HTML documents, images, scripts, stylesheets, and other resources needed to render the webpage in the user’s browser. This process involves multiple HTTP requests and responses for each element that makes up the webpage, ensuring that all necessary content is delivered and displayed correctly.
HTTP connections function by establishing a TCP connection between the client and the server. The client initiates the connection by sending a TCP SYN packet to the server, which responds with a SYN-ACK packet. Once the connection is established, HTTP messages (requests and responses) are transmitted over this TCP connection. After transmitting the necessary data, the connection may be closed by either party or kept open for subsequent requests, depending on HTTP version and server/client configurations.
An HTTP request begins when a client (e.g., a web browser) sends an HTTP method (e.g., GET, POST, PUT) along with a URL (Uniform Resource Locator) to a server. This request method specifies the action the client wants the server to perform on the specified resource. Additionally, the request may include headers that provide additional information about the request, such as the type of content the client can accept or authentication credentials. Once the server receives the request, it processes the request based on the specified method and URL, retrieves the requested resource, and prepares an HTTP response to send back to the client.