File Transfer Terminology

Client
A client is a computer application that you use to connect your local computer to a server on the internet. In this case, the client is FileZilla Pro. Using it, you can add, delete, or edit files and/or directories on the remote server.
Server

A server is a computer that you can connect to via the internet. Servers can be used for a range of activities, but for purposes of FileZilla Pro, they’re used for uploading and downloading files. For example, a website is generally hosted on a server or cluster of servers, and you can connect to it via its FTP server – a computer dedicated to handling file transfers.

Note If you want to create an FTP server, you’ll need FileZilla Server.

Overwrite
Copying over an existing file with one of the same name and file extension. This is a term you’ll come across often in FileZilla Pro documentation, because it’s common while copying files to come across files that you or someone else have already copied across, and you’ll need to tell FileZilla Pro how to handle this situation. One option is to copy over the existing file with a new one that has the same filename.
Queue
The queue – or transfer queue – is a list of files and directories that FileZilla Pro has been told to transfer from one computer to another, but which haven’t yet been transferred.
Recursive
In terms of FileZilla Pro, a recursive action on a directory affects all of its subdirectories and files in them. For example, running a delete command on a directory with a number of files in it as well as subdirectories with files in them – perhaps several levels deep – requires FileZilla Pro to first send a delete command for each file in the bottom layer of directories, then send a delete command for those directories, then send a delete command for files in the second-to-bottom layer of directories, etc, until it reaches the top layer of directories and files.
Bookmark
Bookmarks in FileZilla Pro save the locations of directories on remote servers. You can use them to save time in navigating complex directory structures. They’re especially useful for directories that you use frequently. See Bookmark a Directory for more information.
TLS
Transport Layer Security (TLS) encrypts communications between FileZilla Pro and a server. This keeps the files that you’re transferring secure from eavesdroppers while they’re in transit between your local computer and the server. TLS is used in FTPS connections.
Local
The machine on which FileZilla Pro is installed, that you’re using to control file transfers.
Remote
The server that FileZilla will connect to in order to modify directories and files. Often this is geographically remote as well.
MIME Types

MIME stands for Multipurpose Internet Mail Extensions, and it’s a technique that servers use to recognise the type of file being used, similar to the way Windows recognises files by their file extension (eg .txt). It helps browsers to figure out what to do with a particular file when you click on a link to it; for example, display it or download it. A MIME type typically consists of a type and a subtype.

Common MIME types are:

  • text
  • image
  • audio
  • video
  • application
Upload
When files are transferred from a local machine to a remote server.
Download
When files are transferred from a remote server to a local machine.
Simultaneous connections
Every time that FileZilla Pro sends a request to a server, it needs to have an active connection open. As it can only send one request at a time over a single connection, FileZilla Pro can open multiple connections with a server so that it can send more than one request at a time. Effectively, this can mean several file transfers happening simultaneously.
SFTP
SSH File Transfer Protocol is a method that FileZilla Pro can use to access and transfer files on a server. It’s based on Secure Socket Shell protocol rather than traditional File Transfer Protocol, so it tends to use a server’s SSH port.
FTPS
File Transfer Protocol with TLS is a secure version of File Transfer Protocol (standard FTP). File transfers are encrypted between FileZilla Pro and the server.
FTP
File Transfer Protocol is a basic method for moving files between local and remote computers. See FTP for more information.
User ID
Also sometimes referred to as a User Name or User Identification. This is the string of text that an application, server, or website recognises as belonging to a particular person. Sometimes your user ID will be your email address; sometimes just a string of characters, for example janesmith98352.