| • | This is RAM that appears between address 0 KB and address 640 KB (in the motherboard's address space). |
| • | Also known as 'base' memory, a term that IBM was known to use (at the time of the IBM AT). |
| • | Conventional memory must start at the 0 KB address, and be contiguous (no gaps). |
| • | The WikiPedia article is here. |