What Is an API, and How Do Developers Use Them?

An intriguing fact about API is that this idea originates from 1940. API as “An application programming interface” reached its peak in 2000 and continues to be an inevitable part of web communication between developers since.

Today, we recognize four main types of APIs:

1. Open API

Open API (public API), can be used by developers to share data openly.

2. Partner API

This API is used between companies that share business relationships. Only authorized partners (official licensees) can use these APIs and access company resources.

3. Internal API

Internal APIs are known as private APIs, and they are used only inside one company. Developers who work for a specific company using internal APIs can transfer data between teams and systems in that company but can’t share them with third parties.

4. Composite API

This is a combination of multiple APIs, and this type of API is deployed in microservices. Composite APIs reduce system complexity and can be set as an automatic chain of calls and responses (this can create faster systems).

Developers and API usage

There are numerous benefits for developers when they use APIs. As previously mentioned, API is a communication channel between the user’s computer and the server. To be more precise, it is a data transmitter.

The main benefit of APIs for developers is that they have aces to already-created software solutions, and use them to speed up the software creation process. The developer using APIs will request a software piece and integrate it into his new project. It will save a lot of time and speed up software development productivity. By using once-created software or tool, there is no need to write code and spend time on a feature already created by another developer.

API (application programming interface) integrates two components: Specification and Interface.

– Specification component is the technical part where data exchange details are described.

– Interface is a communication component, and the commonly used API interfaces are REST, API, and RPC.

These two API components determine types of user connections thru API: operation types, input data types, and output data types. Let’s say that API is a form of contract that needs to be respected.

How can developers use four types of APIs?

– Open API usually allows free access to developers and provides access to all publisher’s features. This API is popular with startups as a way of promotion, and a kind of “invitation” to developers to use the software and tools they created.

When a company has public API, it can apply more security features and ensure that its users are protected.

Good examples of open APIs are Google Places API, Twitter API, Google Analytics API, Upwork, and Spotify APIs.

– Internal APIs are used in the company by its in-house developers. It is still a “communication between software products”, but the source code is company owned. Third-party developers don’t have access to this kind of API, and developers who are employed by the company use internal API when creating CRM, ERP, or HRS enterprise-level software.

In-house developers using internal APIs will easily reuse codes and be more efficient. And the company project they work on will follow the best practice of an agile project.

– Partner API model is a revenue one. It operates under paid accesses or one that requires detailed info on third-party projects. This access, if considered suspicious or unsafe, can be declined.

– Composite APIs are very complicated to use. These APIs are offered under different distribution models. As designed to request access to different endpoints in a single call, this API type is recommended only for very experienced developers.

Final thoughts

APIs are used more and more in the software development process. Professional developers use APIs in all phases of their software creation. Startup companies and their developers see APIs as an excellent opportunity for free publicity and promotion of their products. APIs are also an important part of security processes, but this can be another topic to discuss.