Through API Testing what exactly do we verify?

In API Testing, responses based on the following parameters will get analyzed.

• Testers or developers have to analyze the data accuracy which they have received by comparing it with the expected response.
• Time is taken by the API to respond.
• Error codes need to be analyzed if APIs are expected to throw an error.
• HTTP status codes.
• Non-functional specifications like the security, performance, availability, etc. of an application need to be tested.
• Authorization checks