Basics of networking

Another type of message is a POST message, which is used to send data to a server. For example, when there is a form on a page that sends data to the server, such as a registration form, the data we put in it is sent with a POST message.

Although the HTTP protocol is very popular and probably the most widely used of all application layer protocols, it is not secure. The POST method sends data to the server in plain text. If the transmission between client and server is intercepted, it is possible to read the information you want to send to the server.

This is very dangerous, which is why nowadays most websites can send some information to the server, e.g. those sites that require a login already use HTTPS, which encrypts the communication between the client and the server, running on port 443.

Other types of messages that clients can send to the web server are:

Remove: the request to remove the resource from the server

Head: requests resources from the server in the form of headers

Link: request establishes relationships between existing resources

Options: requesting the server to identify supported methods

Put: requests the server to receive the file from the client

Trace: requests the server to return the headers of the message sent by the client.