It is used to execute a command whilst suppressing normal shell function lookup.
Built-in functions take precedence over programs when resolving the name of a command.
A user may suppress the lookup of built-in functions in order to execute a program with the same name as a built-in function.
In all other circumstances the command will be processed as normal.
[2] In the following, the ls command is run without any shell functions or aliases that may exist with the same name: