This topic describes how to make API requests and is intended for users who initiate HTTP or HTTPS GET requests by calling API operations based on URLs.

Note If you are using SDKs, Alibaba Cloud CLI, or OpenAPI Explorer, skip this topic.

The request URL consists of different parameters and has a fixed syntax. The URL contains common request parameters, your signature, and operation-specific parameters. Unencoded sample URL requests for every operation are provided for your reference. You must encode your URL before you submit a request. After the the request is verified based on your signature, the results are returned to you. Response parameters are returned if the call is successful, whereas error messages are returned if the call fails. You can troubleshoot issues based on the common error codes and operation-specific error codes.