# Glossary

| Name    | Definition                                                                                                                                                                                                      |
| ------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| API Key | The [key that you use to access our Crypto Ramp API](/docs/api/crypto-ramp). It's different for Test and Production environment. Be careful not to share it with unauthorised parties.                          |
| OTP     | One-time password. A unique code generated for each relevant operation (e.g. logging in, confirming a payment) and sent to you, which you enter to confirm that it's really you who's performing the operation. |