FTP, HTTP, SSH

FTP

FTP stands for file transfer protocol. It commonly runs on port 21. FTP is used to share files between computers. To transfer files you will typically use a FTP client like FileZilla.

HTTP

HTTP stands for Hyper Text Transfer Protocol. It's used primarily to fetch web resources on port 80. It utilizes TCP protocol, so each request needs to compelte a 3-way handshake. The downside of HTTP is that communications are sent in plain text and can be intercepted and read. The solution to this is to utilize secure HTTP, or HTTPS. HTTPS is HTTP secured by an SSL certificate. This encrypts the data that is communicated over port 80.

SSH

SSH stands for Secure Shell. It is used from remote login protocol, which utilizes TCP. It's a huge improvement over telnet because it sends data in encrypted format. SSH commonly runs on port 22. Like FTP, files can be transferred between the Secure Shell Connection.