# Getting Started

## Preparation

Before you use API, you need to login the website to create API Key with proper permissions.

You can manage your API Key in UI or by [Authenticating API](/rest-api/authenticating.md). See the [Authentication Guide](/guides/authentication-guide.md)

Every user can create API Keys, each can be applied with either permission below:

* Read permission: It is used to query the data, such as order query, trade query.
* Trade permission: It is used to create order, cancel order and transfer, etc.
* Withdraw permission: It is used to create withdraw order, cancel withdraw order, etc.

## Issuing API Credentials

You can get your API credentials after passing verification process. You need to reach Level 3. That requires your email & phone to be verified, enable 2FA enabled and complete KYB.

![](/files/-Mejps87YDr-HVxVaJJn)

Interface Type

There are two types of interface, you can choose the proper one according to your scenario and preferences.

### REST API

REST (Representational State Transfer) is one of the most popular communication mechanism under HTTP, each URL represents a type of resource.

It is suggested to use Rest API for one-off operation, like trading and withdraw.

### WebSocket API

WebSocket is a new protocol in HTML5. It is full-duplex between client and server. The connection can be established by a single handshake, and then server can push the notification to client actively.

It is suggest to use WebSocket API to get data update, like market data and order update.

**Authentication**

Both API has two levels of authentication:

Public API: It is for basic information and market data. It doesn't need authentication.

Private API: It is for account related operation like trading and account management. Each private API must be authenticated with API Key.


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# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.nebulaecn.com/getting-start.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.