The difference appears to be that "Command line interfaces" are generally shorter commands than ones in a graphical User Interfaace

Command line interfaces appear to be a "shorthand"  version of Graphical user interfaces which is why they are called "Command line Interfaces" instead.

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Comparison to graphical user interfaces

Comparison to graphical user interfaces

Screenshot of Apple Computer's CommandShell in A/UX 3.0.1

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 scripting language that can take parameters and variable options. A command-line history can be kept, allowing review or repetition of commands.
A command-line system may require paper or on-line 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.