File Update Synchronization A network service that keeps track of different versions of the same file. If two clients open a file at the same time and then try to save the changes that each have made, one file will overwrite the other. File update synchronization co-ordinates this problem so all changes are applied to the file regardless of how many versions are open. The data is stored in a container called a file. Filter A piece of software that an application uses for file-format conversion or special effects.
Filters can be part of the main application or external programs called plug-ins.
Finger An Internet tool for locating people on other Internet sites. Finger is also sometimes used to give access to non-personal information, but the most common use is to see if a person in online at a particular Internet site. Firewall A firewall is a combination of hardware and software that many companies or organizations have in place between their internal networks and the Internet . A firewall allows only specific kinds of messages from the Internet to flow in and out of the internal network. This protects the internal network from intruders or hackers who might try to use the Internet to break into those systems.