Application programming interfaces (APIs) are an essential component of the technological landscape. APIs provide a common language and contract that enables two systems to communicate. Furthermore, we use APIs to request information from other websites and applications. Developers can save time and energy by using APIs instead of creating their own scripts and programs from scratch. Also, APIs help to improve the user experiences of some of the most well-loved applications. Likewise, using a blockchain API for Web3 development saves developers time and resources. Plus, it means they don’t need to create their own networks each time they want to interact with the blockchain. So, if you’re one of the many crypto enthusiasts wondering, “what is an API?” – read on!

In this article, we’re going to dive deep into the world of application programming interfaces. We’ll answer common questions surrounding APIs, such as “what is an API?” and “how does a blockchain API work?”. Also, we explore some of the different types of APIs, how they work, and the differences between them. Additionally, we discuss the advantages of using a blockchain API when building Web3 applications.

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What is an API?

So, what is an API? An application programming interface (API) is a type of software that enables two applications to speak to each other using a predetermined set of protocols and definitions. Most users don’t know it, but whenever you use a social media app or check the weather on your phone, you’re interacting with an API. For example, when you check the weather on your weather app, the app communicates with the weather bureau’s database via an API to keep you updated.

Furthermore, APIs make life easy for developers by removing a lot of the legwork involved with enabling applications to communicate with each other. When interacting with an API, developers can browse a list of operations with descriptions of how they function. They don’t always need to know exactly how every operation works, just that it’s available for them to use in their application.

Moreover, APIs help to optimize the development process and expedite innovation. Using APIs allow developers to save time and use less code to build applications. Additionally, APIs can facilitate consistency between multiple applications and control over resources.

How Do APIs Work?

Now that we have addressed the question of “what is an API?”, let’s dive a little deeper and see how APIs function in real terms. If you’re developing a new app or program and want it to feature a web browser, you can use an API to embed a webpage instead of programming it from scratch. Likewise, if you take photos on your iPhone, you’re not required to write a camera interface from scratch. Instead, you will likely use a built-in camera API that embeds the images captured from your camera into the camera app. As such, any developers creating an iPhone app that uses the camera on your phone benefit from the camera APIs created by Apple developers. This means they can spend more time developing their app and less time repeating common processes.

Furthermore, when you use an app on your phone, the app communicates data to a server via the internet. After interpreting all of the relevant data, the server performs the actions required by the app before transmitting it back to your phone. The app on your phone interprets the returned data and displays it via a user interface.

To understand this process more practically, let’s look at a common analogy used to describe how APIs work. If you’re sitting in a restaurant waiting to order from a menu, you can think of the kitchen as the system or database that will prepare your food. However, the kitchen requires an intermediary to communicate your order to them and bring it back to your table. In this example, the waiter or waitress is the API, and your menu order is the API call.

Endpoints and Security

An API endpoint sits at each side of the communication channel used in an API request. Furthermore, most API endpoints can feature a server or service URL and act as locations from which data is requested for a specific function. Each time an API requests data from a web application or server, it is sent to an endpoint for a response. Moreover, endpoints help us to specify the location of the resources we need to answer an API request.

APIs also play an essential role in security. This is because they can control hardware access and software permissions. When a website requests to know your precise location, they’re likely trying to use your web browser’s geolocation API. Also, because the website can only learn your location via this API, users can confirm or deny any requests.

Different Types of APIs

Though there are multiple ways to categorize APIs, we can learn a lot about an API by looking at the application that sends the request to it (client) and the application that replies (server). Many APIs are broadly separated into four groups according to their purpose. 

First, simple object access protocol (SOAP) APIs are legacy APIs that require clients and servers to communicate in XML. Second, remote procedure call (RPC) APIs involve clients completing functions on a server before the server communicates an output back to them. Third, WebSocket APIs rely on JSON objects for two-way data communication between client apps and servers. Finally, representational state transfer (REST) APIs are one of the most common APIs for web development. REST APIs involve clients communicating data requests to servers in a way that doesn’t require servers to store client data.

Although the four types of APIs mentioned above cover many of the common APIs around today, multiple subcategories of APIs and bespoke APIs fall into their own categories. Also, there is a lot of crossover between APIs. For example, REST APIs are enhanced versions of Web APIs. Web APIs allow website servers and web browsers to communicate. Every web service can be categorized as an API. However, not every API is a web service. Many APIs were developed before the internet as we know it. As such, many of the terms you’re likely to associate with APIs are interchangeable.

As discussed above, APIs can be categorized as per their architecture. APIs can also be defined by how we use them. For example, enterprises use private APIs for communicating data between company systems. On the other hand, public APIs are available for anyone to use. Furthermore, composite APIs use two or more API types for nuanced system processes.

What is a Blockchain API?

So, what is a blockchain API? In the world of Web3, it would be far too impractical for every network participant to create their own network when they want to interact with a blockchain. Thus, blockchain APIs allow users to communicate with blockchain nodes and client networks via third-party services. For example, when a website such as CoinGecko displays the prices of different cryptocurrencies, it relies on multiple APIs to gather price feeds from crypto exchanges. Accordingly, using a blockchain API enables Web3 developers to create novel applications that would be impossible using blockchains alone.

Furthermore, there are multiple uses for blockchain APIs. For example, you could use a blockchain API for security, to retrieve real-world data for use in decentralized applications (dapps), or to retrieve metadata for non-fungible tokens (NFTs). Blockchain APIs facilitate secure cryptocurrency transactions on exchanges and smart contract interactions for decentralized finance (DeFi). Plus, they facilitate seamless user experiences that promote the adoption of Web3 technologies.

Just like Web2 APIs, blockchain APIs allow users to interact with applications without the need to create new software every time. Moreover, blockchain must be accessible and usable for it to become mainstream. Accordingly, blockchain APIs play a crucial role in lowering the barrier to entry for Web3 users and expediting innovation in Web3 development.

Why Use a Blockchain API?

Blockchain APIs help businesses sector-wide to integrate Web3 technologies for all kinds of use cases. Whether you want to accept crypto payments, connect to an NFT marketplace, or access decentralized file storage on the blockchain, APIs can help you get there faster. Likewise, if you’re building a decentralized application that requires data from outside the native blockchain, an API could help you achieve your goals in less time. Furthermore, using an API to connect to public blockchains could help developers and businesses future-proof their applications, websites, and computing systems and join the Web3 revolution.

The Moralis Web3 API

The Moralis Web3 API is an ultra-fast, versatile, powerful, and cross-chain blockchain API. It enables users to query data from any blockchain. Whether you’re fetching data regarding transaction info, NFT metadata, token prices, user balances, or any other EVM blockchain data, Moralis’ blockchain API is the ideal solution.

As you might expect from an industry-leading blockchain API, the Moralis Web3 API makes the development process incredibly straightforward. Also, all of the Web3 API functions can be called using just a few lines of code. Furthermore, even if you have just basic programming skills, the Moralis Web3 API allows you to create dapps on any of the top chains with minimal friction. Accordingly, you can spend less time on the grueling backend and more time creating fantastic dapps.

That applies to dapps (decentralized applications), NFTs (non-fungible tokens), marketplaces, and much more. If you want to see the Moralis Web3 API in action, check out Moralis Workshops. Here, we provide a range of guided builds for decentralized versions of popular Web2 apps. Previously, Moralis Workshops has featured projects such as a Web3 Skyrim Market, a Sim City Web3, and more! Also, check out the Ethereum Dapp Programming course at Moralis Academy to learn how to build your own NFT marketplace on Ethereum!

What is a Blockchain API? – Summary 

APIs are a form of intermediary software that enable applications to communicate with minimal friction. Generally speaking, APIs feature a range of subroutine definitions and communication protocols. Also, they boast a range of tools to optimize the development process and allow developers to create new applications using the functionality of existing ones.

APIs are a critical component of modern technology, shaping the way it evolves and the ways in which we use it. Without APIs, developers would need to reinvent the wheel each time they make a new application. Furthermore, users would require technical knowledge of every app they use, making it difficult for new technologies to catch on. Blockchain APIs allow us to interact with multiple blockchain networks with minimal friction. Also, developers benefit from using a blockchain API, saving them time and resources. After reading this article, when someone asks you, “what is an API?”, you should be able to answer confidently. You should understand why APIs are so crucial to modern technologies and what makes them so useful in our daily lives.

Blockchain developers are in high demand and can command a handsome salary. If you want to become a blockchain developer but don’t know where to start, check out the JavaScript Programming 101 course at Moralis Academy. Regardless of your coding experience, this course teaches you how to build a decentralized exchange (DEX) on Ethereum from scratch. Take your programming game to the next level today with Moralis Academy! 

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