What is a REST API?

What is REST API style

REST (Representational State Transfer) is an architectural style for designing decentralized systems. It originated from an architectural analysis of the Web and combines a client/server architecture with additional constraints that define a uniform interface.

Since an API (Application Programming Interface) is a set of rules that lets programs converse interact (it defines the rules of communications between applications), REST as a style puts some constraints on what an API will look like.

With REST APIs, you have guidelines that developers adhere to when they create an API. The end result is that API users can get a part of the data when you link to a specific URL. The individual URL allows us to make a request and the data that is sent back is the response.

  1. What are the possible technologies for REST?
  2. How do REST APIs work?
  3. REST API Example
  4. REST APIs Uses
  5. REST API vs API
  6. Why are REST APIs Important?
  7. What was used before REST APIs?
  8. REST vs SOAP
  9. What are the True RESTful APIs?

What are the possible technologies for REST?

Technology is the foundation of any REST APIs since REST is just an architectural style and therefore does not require any specific technology. But of course, the underlying technology of REST APIs must match the general constraints of REST, such as being a client/server protocol. Using well-known protocols makes it simpler to be easily usable by developers. Simple designs work best and mean that APIs can work easily with most programming languages.

The basic technologies used for REST APIs are HTTP, OAuth, JSON/XML, JWT, and Webhooks. These are the go-to and favored technology for API consumers—as well as providers—due to the effortlessness, safety, as well as the ability to make resources and data available. This makes it much easier to incorporate into web and mobile applications.

REST API: How do they work?

A REST API works by breaking down an activity. This generates a sequence of small components, while each component will tackle a specific part of the activity. Flexibility is allotted from this component, but challenges can certainly arise.

REST APIs use prevailing HTTP procedures. They use GET to get back a resource; PUT to change the state of the API or modernize a resource. All API calls are stateless. This means that nothing can be held by the RESTful service between implementations.

What is a REST API example?

The Twitter API comes to mind. It’s a sound example because it implements the REST API. The Stripe API is also used quite frequently due to the advanced features like enlargement and pagination. It’s a well-used model of how REST APIs work. The Slack API is also used with REST APIs and GitHub API v3. Stress-free utilization makes it quick to implement.

Other popular examples to consider are Google APIs. Google has many uses with its APIs including YouTube API, Google Analytics API, Google Font API, Blogger API, plus many more. They all use REST APIs as part of their technology. Other social media platforms using APIs such as Facebook and LinkedIn are using REST APIs.

What are the uses of REST APIs?

REST APIs have many uses because the API calls are stateless. They can also be beneficial in cloud applications. Cloud computing and microservices are on the road to making RESTful API design the directive for the future.

Stateless elements can be easily redistributed is there is a failure on hand. Another use is that they can measure to adjust for load changes. The reason being that any specific request can be pointed to any request of an element. Nothing can be saved that has to be in memory for the next transaction. This makes REST APIs the go-to component for web use and cloud computing.


Rest API and an API may sound similar, but they are a different ball of wax. API is more the King of the world while REST API is the Queen. Two different categories! One is the top and one is second in command. An API is a general term, but a REST API is more specific.

APIs are the glue that connects one application to another with services and data getting access. The difference lies is that REST APIs are a web-service API or architectural style which utilizes HTTP protocol and JSON for data format. REST APIs bring about simplicity in development with limited resources and requires less protection.

Why is REST API important?

REST API is the mainstay of service app development. It’s simple to use and has a global standard in the creation of APIs for Internet services. REST is any crossing point between structures using HTTP to get hold of data and produce operations on the data in all probable formats.

What was used before REST API?

Before REST API, which was the brainchild of Roy Fielding, SOAP (Simple Object Access Protocol) was used to integrate APIs. Since REST API was not on the API scene years ago, it was quite difficult to build and clumsy to use. There was another version called CORBA, but that was not much better.

The early days of APIs didn’t have all the technology that is available today and there was no real gold standard for how these APIs should be developed and used. But thanks to Roy Fielding who came up with the concept of REST APIs, the level playing field had become a whole new world.


REST (Representational State Transfer) is an architecture style while SOAP (Simple Object Access Protocol) is a protocol.

REST API has the advantage of being able to use the SOAP protocol. So, they are featured differently and certainly work in a diverse function. SOAP is also known to have tighter security features which are a plus.

Other differences are REST APIs access a resource for data (URI) while SOAP operates. REST also handles different data forms, HTML, XML and JSON, where SOAP only uses XML. Also, SOAP needs more bandwidth to operate and REST needs fewer resources. Because REST is mainly for web services, being lightweight is a plus. Note that REST can be cached, SOAP doesn’t have this functionality. In the end, the differences are unique, there’s no real comparison is the bottom line.

What are the true RESTful APIs? (Six architectural constraints)

REST APIs have six architectural constraints. This makes any web services a true RESTFUL API.  

  1. Uniform interface
  2. Client-server
  3. Stateless
  4. Cacheable
  5. Layered system
  6. Code on demand (optional)

Uniform interface

The uniform interface control is necessary for the design of any REST service because it makes it easy to use and decouples the architecture. This lets each part evolve on its own.


The Client-server allows the client application and server to be able to advance individually. Only utilizing resource URIs makes it simple and is common practice.


Stateless is when the computer or program follows the status of interaction. This means that there is no record of prior communications and that the request was handled on an individual basis.

The outcome is that the server will not store data that the client made. Each request is individual and is treated as such. No meeting, no history.


In the world of REST APIs, being cacheable brings improvement to performance for the client. This brings better scalability for a server because the load has been decreased. The bottom line is a well-run cacheable machine helps to eliminate interactions that impede performance.

Layered system

A layered system allows you to take layer upon layer with different units of functionality. Basically, as the name states, you have a way of communicating with each layer to have functions performed to its specifications.

Code on demand (optional)

Most of the time, code on demand can be optional. Code on demand allows you to execute a real REST API and a server can increase the ability of a client on runtime.

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