FileZilla is a free, open source FTP client, with versions compatible with Windows, Mac, and Linux. FileZilla supports the use of FTP, SFTP, and FTPS (or FTP over SSL/TLS). This free yet powerful program is useful for regular FTP users who need a good, free option to transfer files. It's simple to setup and run, and it gets the job done. It has a very straightforward and user-friendly interface. It allows you to quickly drag and drop files from your computer to the server, or vice versa. It also allows you to set how many simultaneous uploads or downloads you want to run, making file transfer faster.