React has been growing in popularity and has become the JavaScript flavor of choice for many programmers due to its ease and speed. But what exactly is React, and what is React used for? This article will dig into what React is and how it creates effective user interfaces (UIs).

What is React?

React, also known as React JS, is a JavaScript library used to develop user interfaces. The user interface is what you interact with when you use a site or application. For example, think of when you rate a service by giving it five out of five stars. A developer may have used React to build the icons you selected, to dictate how the stars respond when you select them, or to determine how the data related to your choice is collected and used by the site.

As mentioned, React is a JavaScript library. Let’s break that down. JavaScript is a programming language used to develop websites. In the context of web design, a library is a collection of prewritten code. You can use these prewritten snippets of code to execute common functions in JavaScript. You can learn how to program with JavaScript in our Learn JavaScript course.

What is React used for?

React speeds up the process of creating user interfaces due to its diverse assortment of prewritten code. You can use this prewritten code to design a wide range of interactive functions in JavaScript more efficiently. Here are some examples of what React is used for:

Allowing users to interact with and view images

With React, you can design how users see images and what happens to them on the web page when users take specific actions.

For example, you can set up a carousel of images that automatically rotates, showing the next image when the user clicks the right or left edge of the image. You can also decide whether to incorporate arrows indicating whether the user is going to the next image or the previous one.

Manage how text appears on a page

When a page needs to display text — either text entered by an end-user or inputted by the page’s designer — React can be used to ensure it fits within a specific area.

For example, if you need a user’s name to fit inside the user’s avatar, you can use code from the React library to ensure the text is sized correctly and doesn’t overlap the edges of the avatar. You can also designate a specific space within the avatar for the text to go, so it doesn’t cover the avatar’s image itself.

Pick date ranges on a calendar

If you’ve ever used a booking website and had to choose dates for visiting an area, staying at a hotel, or flying round trip, you may have been using an interface designed with React. React can make it possible for the end user to choose the time frame or number of days and include features that allow dates to be highlighted when users hover over them.

Select items from a column of choices

React can be used to enable users to choose options from a column on the left and shift them into a column on the right that indicates the options they are interested in. The positioning of the columns — left/right or right/left — can also be adjusted, as can the buttons the user clicks on to indicate their choice.

In addition, React can decide what happens during the selection process. For example, a button can change color when the user hovers over it, or a choice can be highlighted after it has moved from one column to the next.

Automatically generate charts

With React, you can include automatic chart generation within a web app. You can generate a chart from input coming in from a variety of data sources. Charts can then be rendered as an image that the user can download.

A chart’s colors, formatting, spacing, and other aesthetic elements can automatically be set using React.

Design input fields for web apps

React can make it easier for end users to enter information in data fields on a web app by including features that make data entry more convenient. For instance, you can use React to set up rules that interpret abbreviations as numbers, such as “k” for 1,000 or “m” for 1,000,000. You can also give users the option of deciding the currency symbol they would like to use. If there needs to be a limit on the value of what users can enter, you can use React to set maximum and minimum values.

Create interactive map views

Using APIs, such as Google’s map API, you can use React to alter how a map looks to an end user based on the choices they make. For instance, you can make the map larger or smaller as the user zooms in, or you can display more or fewer street details and landmarks depending on the zoom level.

Because React features prewritten JavaScript, you can potentially use it to do anything JavaScript can do. In addition, React is open source, so with the right knowledge, you can create your own solutions and have them included in React’s library.

To get started coding with React, you can enroll in our Learn React course. With our courses, you’ll not only get the knowledge you need to code in React and other leading languages, but you’ll get the experience needed to create a compelling portfolio to begin your career as a programmer. Get started for free today!

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