computer

1. hardware

1.1. input

1.1.1. keyboard

1.1.2. mouse

1.1.3. microphone

1.1.4. scanner

1.1.5. pointer

1.1.6. joystick

1.2. output

1.2.1. moniter

1.2.2. speaker

1.2.3. printer

1.2.4. projecter

2. software

2.1. program

2.1.1. browser

2.1.2. game

2.1.3. doccument

2.2. OS

2.2.1. window

2.2.2. mac OS

2.2.3. Linux