FTP is one of the many three letter acronyms you are likely to come across in everyday computing life. It stands for file transfer protocol, and is a fairly geeky term that describes the technology used for copying a file from one computer to another via the internet. Using FTP software, you can upload a file to another computer, then download that file to another machine.

If you've not come across the term FTP before, your first reaction might be: 'But that's what email is for!' And you'd be correct. Email is widely used to transfer files between people. FTP doesn't duplicate this function; it offers an entirely different set of functions.

Anyone who manages a website will probably use an FTP server to upload files from their local PC to the machine that holds and provides user access to the website. They might use dedicated software for this task or, as we demonstrate in our walkthrough, perform the transfer through a browser.

I frequently used FTP when I was writing Brilliant Laptops. Rather than email across completed text and images, I uploaded them directly to the publisher's computer system using FTP. This made it easy for several people to access the files at once.

FTP can be useful if an ISP or email client restricts the size of files that can be transferred. A client of mine has a 10MB limit on individual emails, for example, so I use Dropbox when I need to send larger files. Dropbox isn't an FTP server or an email client, but it's a great alternative for sharing files. Another great alternative is YouSendIt.

Step by step

In the following workshop, we'll show you how to set up and use an FTP server using FireFTP, a free plug-in for the Firefox web browser.

Step 1. There are several ways that you can upload a file via FTP. Many free and paid-for dedicated client programs are available, or you can simply use your web browser. Here, we'll use the free FireFTP Firefox plug-in to transfer files. Click Add-ons in Firefox's Tools menu, then search for FireFTP.

Step 2. Select FireFTP in the list of available add-ons and click the 'Add to Firefox' button. When the installation options box appears, click Install. Installation takes only a few seconds, after which you'll be prompted to restart the web browser to complete the changes. Click 'Restart Firefox'.

Step 3. Open Firefox and click Tools, FireFTP to launch the add-on. A file browser window will appear within the browser, displaying files stored on your PC in the left panel. The right panel will be empty for now, and will become populated with files when you connect to an FTP site.

Step 4. Next, you'll need to create a FireFTP account. Click 'Create an account...' at the top-left of the window. FireFTP requires you to enter some information so it knows how to log into your account. First give the account a memorable name, then add the host, login and password details.

Step 5. You can leave this field blank if you'd prefer to enter your password each time you enter an FTP site, rather than have FireFTP log you in automatically. For FTP sites that don't require a password, use the Anonymous login option. The account name will now appear at the top-left of the page. Click it and choose Connect.

Step 6. You'll notice that both panels in the FireFTP file browser window will now be populated with files. The left panel represents local files, the right displays those stored on the FTP server. You can browse through and open files on either side simply by double-clicking them.

Step 7. Download files from the FTP site by dragging-and-dropping them from the right (remote) panel into the left (local) panel. To upload files to the FTP site, simply drag them from the left panel to the right. This is an ideal way to handle individual files that you might want to share with others or download from the web.

Step 8. Working with remote files is very similar to working with those stored locally. You can hold down Ctrl to select multiple files, and use the right-click menu to cut, copy, paste, create new folders and rename files. A few additional options are provided for advanced users, too.

Step 9. Directly below the local and remote file panels is an activity log, which records file history during the current session. You can make it taller by dragging the frame upwards. If you're uploading or downloading a large number of files, select the Queue tab to get a progress update.

Step 10. If you run a website and want to 'mirror' the files on your local computer with those on the remote one, select the Tools menu and choose 'Sync Directories'. This lets you compare file names and sizes, helping you to identify differences and ensure that your website uses exact copies of the content you have stored locally.

Step 11. If you need to work with several folders, you might find it useful to set up a 'Home' directory, which ensures an FTP session starts at the local and remote locations you specify. Also use the 'Keep directories in sync' option, which ensures both directories follow each other as you move around.

Step 12. Sometimes you need to visit a particular FTP site only once. To save having to set up a login file for that site in your accounts list, FireFTP offers a 'Quick Connect' option. This lets you log in once without it storing the login details. To do this, choose Quick Connect from the box at the top-left.

Step 13. If you want to perform a specific action on a file, you can force it to open in a particular application. Right-click a file and choose 'Open With', 'Add Programs'. Specify the program you want to open a particular file type in. Note that you'll need to browse to the executable file on your hard drive to set this up.

Step 14. If you have several files, you may need to use FireFTP's search tool to find what you're looking for. Select the folder you want to search within, then choose Tools, Search/Filter. Enter your search term in the box at the bottom of the screen; use + to add words, - to exclude words and quotation marks to search for phrases.