A function is basically a named block of code. When you call the function name, the script block within that function runs. It is a list of PowerShell statements that has a name that you assign. When you run a function, you type the function name.It is a method of saving time when tackling repetitive tasks. PowerShell formats in three parts: the keyword 'Function', followed by a Name, finally, the payload containing the script block, which is enclosed by curly/parenthesis style bracket.