Drupal can use a pre-set theme or a customized one. In order to keep things simple for now I will start with the default called "Bartik". Here is regions that are setup in that theme.
| Secondary Menu | |||
| Header | |||
| Primary Menu | |||
| Highlighted | |||
| Featured Top | |||
| Breadcrumb | |||
| Content | |||
| Sidebar First | Sidebar Second | ||
| Featured Bottom First | Featured Bottom Second | Featured bottom third | |
| Footer First | Footer Second | Footer third | Footer fourth |
| Footer fifth | |||