Well, certain inputs like <up> <down> <left> <right> will map directly to keyboard equivalents. The OK button generally maps to <enter>. And then other inputs like play/pause, volume, skip forward/backward are standard PC inputs that just about every OS supports out of the box. Most keyboards have those buttons on them and they “just work”.

For additional functionality you can use specialized software to manage it.

The IR receiver is just a “translator”. The input the computer sees is just a standard HID peripheral (Human Input Device).