What exactly does nodejs do?

On the three major features and applications of Node.js

Node.js is a JavaScript running environment based on the Chrome V8 engine. It is an open source tool that can run JavaScript on the server side. Since its inception, Node.js has been favored by developers and has received a large number of applications and support. However, for ordinary users, what does Node.js do? This article starts with the three major features and applications of Node.js to give readers a comprehensive understanding of this tool.

First, event-driven and asynchronous programming of Node.js.

The most distinctive feature of Node.js is that it is based on event-driven and asynchronous programming. This means that when Node.js runs a program, it will not wait until a certain task is completed or a certain data is read and written before executing the next task. Instead, it will execute the current task while monitoring the execution of the next task. When the next task When you're ready, start executing. In this case, Node.js can greatly improve the efficiency of the program, reduce waiting time, and thereby improve user experience.

For example, writing a web server with Node.js can achieve higher concurrency performance. Traditional web servers generally use multi-threads or multi-processes to handle requests. This method often requires creating a thread or process for each request and maintaining their status, which is not efficient. Using the event-driven approach of Node.js to implement a web server, you can use only a single thread to handle all requests. When a request comes, Node.js will trigger the corresponding event to respond.

Second, Node.js’s non-blocking I/O.

In the traditional I/O (input/output) process, when an I/O operation is performed, the thread usually has to wait. This kind of operation will cause the thread to be blocked, unable to perform other operations, and the efficiency is low. Node.js uses a non-blocking I/O method. When an I/O operation is performed, the thread will not wait, but directly returns to perform the next task. When the I/O operation is completed, it will be called back to process it.

This method can greatly improve the efficiency of the program and save system resources. For example, when we need to read a piece of data from the database, if we use the traditional I/O method, we need to wait for the database operation to complete before performing the next operation. However, using the non-blocking I/O method of Node.js, we can Perform other tasks at the same time, wait until the data reading is completed, and then call back to process it.

Third, efficient modular development of Node.js.

Node.js uses the CommonJS specification. In Node.js, each file is an independent module, and modules can refer to and call each other to facilitate code management and maintenance. At the same time, Node.js also has built-in some commonly used modules, such as http, fs, etc., which can quickly implement some common functions and greatly improve development efficiency.

In addition, Node.js also has a very rich third-party module library, such as Express, Socket.IO, Mongoose, etc. These modules can greatly simplify development difficulty, improve development efficiency, and allow developers to focus more on Business logic.

Conclusion

To sum up, Node.js is an efficient, fast and flexible development tool. I believe that with the continuous development of technology, Node.js will be more and more widely used in various fields. If you are ready to get started with Node.js, then we recommend that you first understand the characteristics and core principles of Node.js to better utilize this powerful tool.

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