Filezilla, great/best FTP and SFTP client for Windows, Mac, Linux
FileZilla is another program I simply would have a very hard time living without. It's simply the one of the BEST FTP/SFTP clients ever, mostly because it works on Windows, Mac OS and Linux.
I use it for my company projects and as a standard practise for my students as a teacher. It's an open source project, which makes it a very available tool. FTP and SFTP/SCP are quite essential for transferring and publishing in the web development world.
The server manager is very useful if you're dealing with multiple projects and thereby webspaces, so you can jump back and forth between them. One of my favourite features is actually that you can have the different connections tabbed, so you can work on multiple servers at once.
The interface might seem a little bit old fashioned, but actually it's fantastic, because of the local files to the left, remote files to the right division.
If you are looking for a solid FTP client with lots of pro features like filtering or default folders upon connection (so you can leave your .git folders out of it, for example).