Attending Web Developer Interviews? You can checkout these important topics on Node.js

Hi Guys, Node.js is one of the promising JavaScript Run Time Environments which is widely used by Web Developers around the world. The support and community for Node.js is steadily increasing over years as many people who depend on MERN Stack(Mongo, Express, React.js, Node.js) and MEAN Stack (Mongo, Express, Angular JS, Node.js) primarily use Node.js as their backend runtime environment.

In this post, I'll help Web Developers/Node.js Developers who are preparing for their interviews with highlighting the important topics in Node.js and also a refresher for developers who would like to brush up their skills. Please do check out my other post which discusses about the important topics on JavaScript Interview Questions below:

JavaScript Interview Questions

Without any further ado, let's get into the topic.

How Node.js works?

This is a common question in Web or Backend interviews which include Node.js as their tech stack. Node.js is a virtual machine that uses JavaScript as its scripting language and runs based on Chrome's V8 JavaScript engine. Basically, Node.js is based on an event-driven architecture where non-blocking I/O runs asynchronously making it lightweight and efficient. It is being used in developing desktop applications as well as provides API to access OS-level features such as file system, network, etc.

Here

• "Event-Driven" actually means that as soon as Node starts its server, it simply initiates its variables, declares functions and then simply waits for the event to occur. In an event–driven application, there is generally a main loop that listens for events, and then triggers a callback function when one of those events is detected. This loop is called Event Loop.
• "Non-Blocking IO" actually means that non-blocking servers – like ones made in Node – only use one thread to service all requests. This means an instance of Node makes the most out of a single thread...

Promises and advantages of Promises over Callbacks

Promises allow you to choose when you want to handle the result of an asynchronous call. Also Promises can be chained, and chains can be extended at any time and it doesn't lead to similar situations like 'Callback Hell'. Along with that Promises allow you to effortlessly handle errors, even when chaining.