# Reference

This section explains the key concepts and terminology used throughout the Nansen API.

### Guides

* Supported Chains - Blockchains supported by the API
* Address Formats - Address formats for each chain type
* Smart Money Labels - Understanding smart money classifications
* Filter Types - Available filter types and usage
* Sorting - How to sort API results

### Quick Reference

#### Chains

The API supports 37 blockchains:

| Type    | Examples                                         |
| ------- | ------------------------------------------------ |
| EVM     | Ethereum, Arbitrum, Base, BNB, Polygon, Optimism |
| Non-EVM | Solana, Bitcoin, TON, Tron, Starknet, SUI        |

#### Smart Money Labels

| Label                     | Description                     |
| ------------------------- | ------------------------------- |
| Fund                      | Institutional investment funds  |
| Smart Trader              | Historically profitable traders |
| 30D/90D/180D Smart Trader | Time-based performance labels   |

#### Common Filters

| Filter Type   | Example                       |
| ------------- | ----------------------------- |
| Numeric Range | `{"min": 1000, "max": 50000}` |
| Integer Range | `{"min": 10, "max": 100}`     |
| Address List  | `["0x...", "0x..."]`          |
| Label List    | `["Fund", "Smart Trader"]`    |

#### Sort Order

```json
{
  "order_by": [
    {"field": "value_usd", "direction": "DESC"}
  ]
}
```


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