Information Technology

The keyboard shortcut used for the “Select all” command is Ctrl + A (or Cmd + A on Mac). This command selects all the contents of the active window—be it a document, folder, or spreadsheet.
Applications include:

In MS Word: selects entire text.
In Excel: selects entire worksheet.
In File Explorer: selects all files in the folder.
This shortcut is a universal feature of modern software interfaces.