104 (5 types)Explanation:Alphabet KeysNumber KeysSpecial KeysFunction KeysNavigation Keys1. Alphabet Keys:  26 alphabet keys are present on a keyboard from A to Z. these keys are not present in the alphabetical order. These keys are used to type words, sentences or paragraphs.2. Number Keys: These keys are used for typing numbers. These keys are present above the top row of the alphabet keys and ALSO present on the right side of the keyboard.3. Special Keys:  Keyboard has more special keys such as SPACE bar Key, caps lock key, backspace key, shift key, enter key, symbol keys and tab key etc.4. FUNCTION Keys:  12 function keys are present on a keyboard. They keys are perform specific tasks. They are present on the topmost row of the keyboard. Label F1, F2, F3, F4, F5, F6, F7, F8, F9, F10, F11 and F12. These keys have different functions for different programs.5. Navigation Keys: Every keyboard has some special navigation keys such as Cursor control keys (Arrow Keys), Home key, End key, CTRL, Alt, Page Up, Page Down, Delete, Insert etc.