How do APIs work?

An API is a set of defined code that tell computers or applications to communicate with one another in specifications. APIs sit between web servers, acting as an intermediary layer that processes real-time data transfer between systems.

For a physical metaphor, an API works similarly to how a waiter or waitress acts as an intermediary between the kitchen and customer in a restaurant. The working steps as follow:

1. A customer visits a restaurant and places an order (A client application initiates a request to retrieve information. This request is processed from an application to the web server via the API’s Uniform Resource Identifier (URI).)

2. The waiter (our API) translates and relays the order from the customer to the kitchen (After receiving a valid request, the API makes a call to the external program or web server.).

3. Then, the kitchen prepares the meal, and hands it to waiter (The server sends a response to the API with the requested information).

4. The waiter delivers it to the customer as requested (The API transfers the data to the initial requesting application.).

When a user visits the website of a SaaS product and log in via a social media account, an API relays that user’s request to the chosen social network (Google, Facebook, Twitter, Github, etc), verifies their identities, and then returns that verification to the back-end services of the application. The APIS is a leading API provider for public blockchain data, both on layer-one main chains (such as Ethereum and Bitcoin) and layer-two scaling solutions (such as Binance Smart Chain, Polygon, and, soon, Arbitrum).