A command-line interface or command language interpreter (CLI), also known as command-line user interface, console user interface and character user interface (CUI), is a means of interacting with a
The CLI was the primary means of interaction with most computer systems on
Command-line interfaces to computer operating systems are less widely used by casual computer users, who favor
Alternatives to the command line include, but are not limited to
Command-line interfaces are often preferred by more advanced computer users, as they often provide a more concise and powerful means to control a program or operating system.
Programs with command-line interfaces are generally easier to automate via
Command-line interfaces for software other than operating systems include a number of programming languages such as
Compared with a graphical user interface, a command line requires fewer system resources to implement. Since options to commands are given in a few characters in each command line, an experienced user finds the options easier to access. Automation of repetitive tasks is simplified - most operating systems using a command line interface support some mechanism for storing frequently used sequences in a disk file, for re-use; this may extend to a
A command-line system may require paper or online manuals for the user's reference, although often a "help" option provides a concise review of the options of a command. The command-line environment may not provide the graphical enhancements such as different fonts or extended edit windows found in a GUI. It may be difficult for a new user to become familiar with all the commands and options available, compared with the drop-down menus of a graphical user interface, without repeated reference to manuals.