FTP - File Transfer Protocol - allows one to transfer files from one computer to another. It is an indispensible tool for web developers. Most (if not all) web hosting packages packages allow developers to put their files on the servers using FTP.

What is FTP?

The File Transfer Protocol is an excellent method to retrieve or send files from one computer to the other on the Internet. Though files can be transferred using email, it is not a good choice if the file size is large or when you need to transfer several files. FTP sites can consist of hundreds to thousands of files with information on books, music, libraries etc.
You can know more about FTP - File Transfer Protocol here.

Below are some FTP clients which I have used. Though these differ in their user interfaces, they all perform the same function, transfering files from one computer to the other.
The advantages of using an FTP clients are several - you dont have to remember FTP commands, the clients can keep a track of which files were transfered thus saving you time, migration through the directories on the server becomes easier etc.

WS_FTP
WS_FTP

CuteFTP
CuteFTP

LeechFTP
LeechFTP

FTP Explorer
FTP Explorer

FTP - File Transfer Protocol
Using FTP with FTP Explorer