What is API (Application Programming Interface)?
An application programming interface (API) is a set of rules and protocols that define how two software systems can interact with each other. An API specifies the functions and methods that one system can use to access and manipulate the resources of another system.
APIs are commonly used to enable different software systems to communicate with each other, share data, and perform common tasks. For example, a website might use an API to access data from a database, or a mobile app might use an API to access a cloud-based service.
APIs can be designed for different programming languages and platforms, and they often use open standards, such as HTTP and REST, to facilitate communication between systems. APIs can be provided by software developers to allow other developers to access and use the resources of their systems, or they can be used internally within an organization to allow different systems to interact with each other.
API (Application Programming Interface) protocols:
There are many protocols that can be used to design and implement an application programming interface (API). Some common protocols include:
- HTTP (Hypertext Transfer Protocol): HTTP is a widely used protocol for communication over the internet. It is used to send and receive requests and responses between client and server systems. APIs can use HTTP to define the methods and parameters for accessing and manipulating resources.
- REST (Representational State Transfer): REST is a software architecture style that defines a set of constraints for designing APIs. REST APIs use HTTP and are designed to be lightweight, stateless, and scalable.
- SOAP (Simple Object Access Protocol): SOAP is a protocol for exchanging structured information in a decentralized, distributed environment. It is often used to design APIs that use Web Services to access resources over the internet.
- gRPC (Google Remote Procedure Call): gRPC is a high-performance, open-source RPC framework that uses HTTP/2 and Protocol Buffers to enable communication between systems. It is often used to design APIs that need to handle large amounts of data or high levels of concurrency.
Types of API (Application Programming Interface)
Some common types of APIs include:
- Open APIs (also known as external or externalized APIs): Open APIs are APIs that are publicly available and can be accessed by any third-party developer. They are often used to allow developers to access the resources of a system and build new applications or integrations.
- Internal APIs (also known as private or hidden APIs): Internal APIs are APIs that are not publicly available and are only intended for use within an organization. They are often used to allow different systems within an organization to communicate with each other and share data.
- Partner APIs: Partner APIs are APIs that are made available to a select group of developers or partners. They are often used to enable collaboration or to allow access to certain resources on a limited basis.
- Composite APIs: Composite APIs are APIs that combine multiple APIs or microservices into a single API. They are often used to simplify integration or to enable the reuse of common functionality.