Understanding the basics of RESTful APIs

Understanding the basics of RESTful APIs


4 min read

As the Internet has grown, so is the need for programmatically accessing and manipulating data hosted by web applications. To enable this access, RESTful APIs have emerged as the preeminent means of communication between web applications and other systems.

What is a REST API?

Roy Fielding defined the REST architecture in his doctoral dissertation 2000 as a new software architecture style for distributed systems. These principles are incorporated into RESTful APIs, providing a standard way to interact with web applications.

REST APIs provide communication between software interfaces over the internet using HTTP protocols. Each request includes all the information necessary to complete the request without relying on previous information requests. It utilizes cacheability, providing a uniform interface and having a layered system architecture.

REST APIs are frequently utilized when building web and mobile applications, as well as other distributed systems. They are commonly paired with technologies, such as JSON (JavaScript Object Notation) for data serialization, and OAuth for authentication and authorization.

Benefits of REST APIs

The standard for communicating with RESTful APIs can be attributed to several reasons namely:

1. Flexibility.

2. Ability to handle large numbers of requests without slowing down or crashing.

3. Possibility of adding new features and functionality without disrupting existing services.

4. Easy to maintain and upgrade compared to other API types.

5. And it is easier to leverage existing web technologies like caching, load balancing, proxies.

How REST APIs work

In a RESTful API, the server shares resources or data, and the client interacts with these by sending HTTP requests (like GET, POST, PUT, and DELETE). The server then responds with the requested data and or a status code.

Let's explore the essential components of RESTful APIs and why they matter;

  • Explanation of resources, methods, and endpoints

  • Discussion of HTTP verbs (GET, POST, PUT, DELETE)

What are Resources?

Resources are objects or entities uniquely identified by a URL or URI, such as a user, product, or order. These data sets can be accessed via endpoints and have relationships with other resources. You can perform a set of allowed operations on them.

What are Methods?

Methods are used to operate resources. They can create, read, update, and delete resources, following the HTTP protocol standards.

What are endpoints?

Endpoints are digital locations from which APIs receive requests about specific resources/da on a server. They provide the location of a resource using a uniform resource locator (URL).


A GET request is essential in RESTful APIs - it's what allows clients to retrieve specific resources from the server. To make a GET request, the client sends a URL that identifies the desired resource to the server. and then responds with a representation of that resource, such as HTML, XML, or JSON.

Importantly, GET requests don't change any resources on the server - they are only meant to retrieve information. This makes GET requests a read-only method. After processing the request, the server responds with an appropriate status code, such as 200 OK for success, or 404 Not Found if the requested resource cannot be found.


A POST request is used to create new resources on the server. It is a write-only method and should be used with caution and above all, securely protected via authentication and authorization mechanisms to prevent unauthorized access or malicious attacks.


A PUT request updates or replaces an existing resource on a server. It should be used when the entire resource needs to be updated or replaced and of course, appropriate security measures should be taken to prevent unauthorized access.


A patch request is used to update only a portion of an existing resource. It applies partial modifications to a resource.

These Put and Patch methods are often misconstrued, so it's important to understand their differences and what they represent.


The delete request is a method used to request the deletion of a specific resource on a server.

They are irreversible and erase the specified resource on a server. This request can be used to remove a user account or delete a comment on a blog post amongst other things.

Case studies on how REST APIs have helped businesses streamline their services

  1. Starbucks: Starbucks' RESTful API is integrated with its existing point-of-sale infrastructure to streamline the ordering and payment process.

  2. Salesforce: Salesforce APIs are used by thousands of businesses to automate sales and marketing processes and manage customer relationships. Developers also build custom applications that extends the platform's functionality which is a win-win for Salesforce.

Strengths of REST APIs:

  1. REST APIs are designed to make it easy for developers of all experiences to use.

  2. They are lightweight, allowing them to perform at a high level.

Weaknesses of REST APIs:

  1. Security: REST APIs rely on HTTP as their communication protocol, which isn't always secure as they are vulnerable to security threats such as SQL injection and cross-site scripting.

  2. Statelessness: While statelessness is one of the strengths of REST APIs, it can also be a weakness since it may require developers to include more data in each request.

Overall, REST is a powerful and widely adopted standard for building web APIs and companies leveraging RESTful APIs can create innovative new products and services, reach new audiences, and improve efficiency and productivity across their organizations.