| Keyword | Definition |
|---|---|
| bit | an individual binary digit |
| laser | light and sound emitting radiation (a focussed beam of light) |
| magnetic surface | covering of a spinning platter inside a hard disk drive which represents 1s and 0s by flipping the polarity of tiny magnetic areas |
| NAND gate | logic gate used in solid state storage devices to represent 1s and 0s |
| pits and lands | bumps on a CD, DVD or BLU-RAY disc which absorb or reflect laser light so it can be detected by a sensor as 1s and 0s |
| polarity | the direction of a magnetic or electric field |
| sensor | a device that can detect something and turn it into an electrical signal |
| transistor | digital switches used to process electrical signals which represent 1s and 0s |
