Arduino 104 key keyboard for common use with pc

[hans00008]

Hello, I am currently working on a project which is a keyboard to a computer, I am using two shift registers for 14 columns, consequently I have 8 inputs on an arduino micro. What always repeats in the loop is that I send 1 to one of the columns for a moment, and then just wait on the output 8 pins, where my 1 apears
Now to the software, so far I'm working on defining an output for each key, e.g. when I press A, according to whether I have schift, capslock or whatever pressed, it will send to the computer according to that, e.g. a, A.
But this is probably not how a commonly used keyboard works, normally I can set keys for many languages, there are many keyboard shortcuts that I don't know how to program, e.g. ctrl+A or alt+F4 :D.
My question is, how does a normal keyboard communicate with a PC and how could one make a "normal" keyboard, with an arduino

[kolaha]

  Keyboard.press(KEY_LEFT_CTRL);
  Keyboard.press('A');
  delay(10);
  Keyboard.releaseAll();

  Keyboard.press(KEY_LEFT_ALT);
  Keyboard.press('KEY_F4');
  delay(10);
  Keyboard.releaseAll();

Keyboard Modifiers and Special Keys - Arduino Reference

[johnwasser]

Start with an Arduino that can act as a keyboard, like a Leonardo or Micro.

A 'normal' USB keyboard tells the PC what key has been pressed. The codes for the keys are defined by the USB standard.

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