Introduction to REST APIs for New Developers

This lesson explains the basics of how APIs work. It introduces the concepts of Client and Server, describes the Request : Response cycle that enables clients and servers to communicate with each other, and then explores API functionality through the lens of a relatable, real-world analogy.

In this lesson, you'll learn about the four parts of an API Request -- verb, endpoint, HTTP headers, and body  -- including:

• The five most commonly used verbs and the purpose of each

• The purpose of an endpoint and how it's typically structured

• The meaning of the term API operation

• The purpose of HTTP headers in an API request, and some commonly used headers

• The purpose and structure of an API request body

• How path parameters, query string parameters, and request body can be used to specify data in an API request

In this lesson, you'll learn about the three parts of an API Response -- HTTP status code, HTTP headers, and body -- including:

• The purpose of status code and the five main categories of status code

• The most commonly seen status codes for each category, and how an API client should react to various codes

• The purpose of HTTP headers in an API response, and some commonly used headers

• The purpose an API response body, and its expected contents for each type of operation

In this lesson, you'll learn about JSON -- the "language" of API requests and responses. Topics covered include:

• How to know if an API request or response body is formatted as JSON

• JSON syntax

• The six data types that JSON supports

• Tips 'n tricks for reading and writing data in JSON format

In this lesson, you'll learn about API security and explore some authentication patterns that you're likely to encounter when using REST APIs. Topics covered include:

• The purpose of Authentication

• The difference between Authentication and Authorization

• Where Authentication and Authorization fit in the typical workflow for API request processing

• Two of the most common authentication patterns: Basic authentication and Bearer authentication

• API access tokens -- what they are, how they're used, methods for obtaining one

• API keys -- what they are and how they're used

This lesson is a series of "live" demos that show real-world APIs in action, illustrating the concepts covered in the course thus far:

• API Requests

• API Responses

• JSON

• API Authentication

API requests are constructed and issued using a popular developer tool called Postman, which also receives and renders the API responses.

In this lesson, you'll learn about the Developer Resources that you'll come to rely upon when using APIs in the apps that you build:

• Developer Centers

• Developer Accounts

• SDKs

• API Docs

In this lesson, you'll learn about three tools that you can use to try APIs without writing any code:

• API Explorer

• cURL

• Postman

In this lesson, you'll learn about four options for getting help (with APIs) when you're stuck:

• Developer (community) forums

• Stack Overflow

• GitHub

• Support

This recap summarizes the lessons learned throughout this course.

This lesson provides additional resources for more great content about APIs.