Question

Which button is known as the Launch Pad

Answer 1

Launchpad is an application launcher for macOS introduced in Mac OS X Lion. Launchpad is designed to resemble the SpringBoard interface in iOS. The user starts an application by single-clicking its icon. Launchpad provides an alternative way to start applications in macOS, in addition to other options such as the Dock (toolbar launcher), Finder (file manager), Spotlight(desktop search) or Terminal (command-line interface). [1]

F4 is known as launch pad