What's the command of call operator &?

The call operator & allows you to execute a command, script or function.

Many times you can execute a command by just typing its name, but this will only run if the command is in the environment path. Also if the command (or the path) contains a space then this will fail. Surrounding a command with quotes will make PowerShell treat it as a string, so in addition to quotes, use the & call operator to force PowerShell to treat the string as a command to be executed.

PowerShell Call Operator

I am not sure of all the operators that are in PowerShell, but another really useful one is --%, used to stop parsing.

The stop-parsing symbol --%, introduced in PowerShell 3.0, directs PowerShell to refrain from interpreting any further input on the line as PowerShell commands or expressions.

PowerShell Stop Parsing Operator

Building on the comments that have been made:

Get-Help About_Operators

It will show you the best overview of all operator types and abstract ones like the Call and Stop Parsing Operators.