In this article we will discuss different types of License Keys that Microsoft uses for its products. They have categorized their customers and provided them with different types of keys. Following are the names and description of Microsoft license keys:
| Product Key | Description |
| CUS | This key is used to activate/install the product. User needs to perform some special actions. |
| MAK | This is a volume license key that allows user to activate the product multiple times. |
| RTL | This key is for retail products and allows multiple activations. |
| STA | This Setup key that is used to bypass the activation process. |
| VL1 | This is VA 1.0 product key. |
| OEM | Origi.nal Equipment Manufacturer (OEM) key allows multiple activations |
| AAA | This is retail key for Academic Alliance and allows multiple activations. |
| AAL | This is Lab use key for Academic Alliance that allows multiple activations. |
| AAM | This key is provided to Academic Alliance Members and allows multiple activations. |
| AV1 | It is VA 1.0 key for Academic Alliance Program and allows multiple installations. |
| AV2 | It is KMS type key for Academic Alliance Programs. |
