An API (Application Programming Interface) is a set of rules and specifications used to communicate between two applications. In simple terms, an API allows one program to interact with another program. For example, you can create an app that lets users send messages to each other through Facebook Messenger. Under the hood, you can use Facebook Messenger API to integrate this functionality into your application using automation to implement these API calls.
What exactly is an API? What does an API Do? API Full Form
What does API Stand for?
API stands for Application Programming Interface. An API (not to be confused with the American Petroleum Institute), an acronym for Application Programming Interface, is a set of definitions and protocols that allow technology products and services to communicate with each other via the internet of things (IoT).
What are APIs used for?
If you are a beginner programmer, you may be wondering what the definition of API is. An API (Application Programming Interface) allows your application to interact with an external service using a simple set of commands. To break down the name, the “Interface” is where different software components can interact. Using an API allows developers to add specific functionalities to their applications and can speed up the development process.
Most of the web applications you use every day rely on APIs in some capacity. There are APIs for nearly every category imaginable, from data to travel and even sports. For example, rather than investing time and resources to create their own payment processing system, many applications use a payment processing API like Stripe instead.
APIs act like building blocks, allowing developers to build applications much faster. They also prevent developers from having to “reinvent the wheel” and spend time creating functionality that already exists.
What does an API do?
In simplest terms, an API acts as a middleman between two or more applications, accepting messages and returning a response. When developing a complex application, we write all of the data manipulation code on the server, which is not accessible to the user on the client side. It is primarily for security reasons. A server is a separate application that is hosted elsewhere.
To obtain data from the server, we must use the server’s API. The API will return a response to the client based on their authentication level.
An API isn’t just for getting data. It can also be used to create, delete, or exchange data on the server.
What are APIs Used For? API Explanation For Beginners:
Essentially, an API allows two software programs to communicate with each other. One program can call another program’s API to get access to data or functionality of the other program.
To understand exactly how an API works, consider this non-technical example. When you go to a restaurant, a waiter will take your order and report it to the kitchen. The kitchen makes your food, and the waiter brings it back to your table.
In this example, one program is you (the person ordering food), and one program is the kitchen. The waiter represents the API that is used to receive requests and return something. In this case, the waiter returns your order, but an actual API would return data or other functionality.
What are Some Examples of APIs? API Examples and Use Case
Now that we have a basic understanding of APIs, it should be easier to see why APIs are so essential in programming. For a slightly more technical example, consider how APIs might play out using a ride-share app as an example. First, you sign up for the ride-share application. Then, you can map your route, find your driver, and pay for the ride all without ever leaving the app.
The ride-sharing app is likely using APIs to make all of this work. For example, an API like Telesign could verify that you own the phone number you provided at sign-up. Calculating the time and distance of the ride is probably done with a maps API. An SMS API like Nexmo could notify you that the driver has arrived at the pickup location. When it’s time to pay, your payment is likely processed with an API like Stripe. Finally, when you get a receipt for your ride, an API like SendGrid sends it to your email.
This is one example of how APIs can be used together to quickly add functionality to an application. To see other API examples, visit the RapidAPI Hub.
What are microservices?
Microservices are an architectural style that structures an application as a collection of small, independent, and loosely coupled services. Each microservice is designed to perform a specific business function and can communicate with other microservices through lightweight protocols, such as HTTP or messaging systems.
Microservices are typically deployed independently and can be scaled horizontally, allowing for greater flexibility and resilience. They can also be developed and deployed using different technologies and programming languages as long as they adhere to common communication protocols.
The benefits of using microservices architecture include faster development and deployment times, improved scalability, better fault isolation, and easier maintenance and updates. However, implementing a microservices architecture also requires careful design and management to ensure proper communication and coordination between the services.
What Different Types of APIs are there?
In terms of architecture, there are five types of APIs:
- REST APIs: REST APIs allow you to perform CRUD (create, read, update, and delete) operations between a client and a server. It provides multiple API endpoints to manipulate data.
- GraphQL APIs: It is a query language that lets clients request the precise data they require from the server. Thus, eliminating the issues of under-fetching and over-fetching that occur in other operating systems.
- SOAP APIs: Any web service that complies with the SOAP web services API specification is a SOAP web service.
- Kafka APIs: Apache Kafka is an event streaming platform that combines three capabilities so that you can implement different use cases. The three capabilities are publishing and subscribing to the streams of events, storing streams of events durably and reliably, and processing streams of events as they occur.
- Async APIs: These APIs work on the principle of Event-Driven Architecture (EDA). In AsyncAPIs, multiple Subscribers can subscribe to a Publisher. When an event occurs, the Publisher (API provider) can notify all the Subscribers via the Message broker.
In terms of access, there are four main types of APIs:
- Open APIs: Also known as Public APIs. These APIs are publicly available, and there are no restrictions to accessing them.
- Partner APIs: These APIs are not publicly available, so you need specific rights or licenses to access them; a good example is APIs shared by a business with business partners to leverage the API capabilities to provide business value.
- Internal APIs: Also known as Private APIs. These APIs are usually meant for use within a company and are only exposed by internal systems. A company can use this type of API across different internal teams to be able to improve its products and services.
- Composite APIs: These APIs combine different data and service APIs. It is a sequence of tasks that runs synchronously as a result of the execution and not at the request of a task. The main purpose of this type of API is to speed up the process of execution and improve the performance of the listeners in the web interfaces.
What are Web Service APIs?
Apart from the main web APIs, there are also web service APIs. A web service is a system or software that uses an address (ex: the URL on the World Wide Web) to provide access to its services. The most common types of web service APIs include:
- SOAP (Simple Object Access Protocol): This is a protocol that uses XML as a format to transfer data. Its main function is to define the structure of the messages and methods of communication. It also uses WSDL (Web Service Definition Language) in a machine-readable document to publish a definition of its interface.
- XML-RPC: This is a protocol that uses a specific XML format to transfer data, compared to SOAP which uses a proprietary XML format. It is also older than SOAP. XML-RPX uses minimum bandwidth and is much simpler than SOAP.
- JSON-RPC: This protocol is similar to XML-RPC, but instead of using an XML format to transfer the data, it uses JSON.
- REST (Representational State Transfer): REST is not a protocol like the other web services. Instead, it is a set of architectural principles. The REST service needs to have certain characteristics, like simple interfaces, which are resources easily identified within the request.
Read to learn more about the difference between SOAP, REST, and JSON.
What are Webhook APIs?
There is another type of API called a webhook API. Webhook APIs function similarly to how a traditional REST API works, but it happens in the opposite direction. Typically, you write a program that will perform an API call and get a response from that API. In some cases, you don’t want to call the API; you just want the API to notify you when something has occurred.
An example of this would be a billing system. You wouldn’t want to have to continuously make a request to an API to see if a payment has been made. Instead, you would use a webhook API to notify you every time a payment is made.
SOA vs. Microservices Architecture
SOA and microservices are two approaches used for developing distributed systems with remote APIs. SOA breaks down functions into loosely coupled components, while microservices create specialized, independent services that communicate using lightweight protocols. While SOA is simpler than a monolithic architecture, it can introduce additional complexity. Microservices support faster feature delivery and dynamic scalability but require careful management to avoid potential issues such as data inconsistency and performance problems. Both approaches have their strengths and weaknesses, and developers must choose the architecture that best suits their application requirements.
What is API Management?
API management refers to the process of designing, publishing, securing, monitoring, and analyzing APIs (Application Programming Interfaces) to maximize their value and potential. It involves various tools, techniques, and processes that enable organizations to control and optimize the use of their APIs across multiple applications, platforms, and devices. Effective API management ensures that APIs are accessible, discoverable, and secure while also providing insights into API usage, performance, and behavior. API management is a critical aspect of modern software development and enables organizations to leverage their APIs to create new products, services, and revenue streams.
What is API documentation?
API documentation is a crucial aspect of API management that involves creating a comprehensive guide for developers on how to use an API effectively. The documentation should be clear, concise, and up-to-date and include code samples and explanations in simple language to help beginners understand the API functionality. Good API documentation should also cover all of the problems that the API can solve for users and ensure that they have all the necessary information to work with the API. By following these best practices, developers can create effective API documentation that helps users integrate and use the API successfully.
Summary
APIs are purpose-built to perform a specific function of allowing communication between applications. APIs have become an integral part of application development. They allow developers to quickly integrate specific functionality into their applications or website. There are thousands of Public APIs on RapidAPI; find the one that will help power your next project on the RapidAPI Hub.
Related terms:
API Gateways
API Requests
