Suggest an editImprove this articleRefine the answer for “What is FTP?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)**FTP (File Transfer Protocol)** is an application-layer protocol used to transfer files between a client and a server over a network. In short, FTP lets you upload files to a server and download them from it. **Key point:** in its basic form, FTP does not encrypt data - the login, password, and files are all sent as plain text.Shown above the full answer for quick recall.Answer (EN)Image**FTP (File Transfer Protocol)** is an **application-layer protocol** used to **transfer files between a client and a server over a network**. In short: **FTP lets you upload files to a server and download them from it**. --- ## Why FTP is needed FTP is used when you need to: - upload files to a server (for example, a website) - download files from a server - manage files on a remote server (create folders, delete files, rename them) FTP used to be **the main way to work with files on servers**. --- ## How FTP works (simplified) FTP uses a **client-server model**: 1. The FTP client connects to the FTP server 2. The client authenticates (login/password) 3. The client: - requests a list of files - uploads or downloads files 4. The server executes the commands and responds People usually use dedicated programs - **FTP clients**. --- ## FTP's quirk: two connections This is a popular interview question. FTP uses **two communication channels**: - a **control connection** - for commands - a **data connection** - for transferring files Because of this, FTP can be harder to configure in networks with NAT and firewalls. --- ## Active and passive FTP modes - **Active mode** - the server connects to the client itself - **Passive mode** - the client connects to all of the server's ports In practice, almost everyone uses **passive mode**, because it works better through a firewall. --- ## FTP's main drawback **FTP does not encrypt data**: - the login and password are sent as plain text - files are transferred without protection So in its plain form, FTP **is considered insecure**. --- ## Secure alternatives to FTP - **FTPS** - FTP + SSL/TLS - **SFTP** - file transfer over SSH Modern systems more often use **SFTP** rather than FTP. --- ## A real-life example FTP is like a remote file manager: - your computer is the client - the server is a "remote drive" - you copy files back and forth --- ## Short answer for the interview A ready-made phrasing: > **FTP is an application-layer protocol designed to transfer files between a client and a server over a network. It lets you upload, download, and manage files on a remote server, but in its basic form it does not provide data encryption.**For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.