What is React?
Whether you're brand new to building dynamic web applications or you've been working with React for a long time, let's contextualize the most widely used UI framework in the world: React.
I still remember when I first heard about React. It was January 2014. I was listening to a podcast. Pete Hunt and Jordan Walke were on talking about this framework they created at Facebook with no support for two way data-binding, no built-in HTTP library, no dependency injection, and in place of templates it had this weird XML-like syntax for the UI. And to top it all off, I was listening to it while driving to the first ever ng-conf. I was so hyped on Angular.js that I didn't really give React.js more thought than: "Huh."
However, a few months later I started seeing some of my friends and co-workers try it out and share why they thought it was interesting. They encouraged me to give it a solid shake. I put it off for a while.
I was busy.
I felt like my current tools were good enough.
But finally, I gave it 5 minutes and that was all it took. I instantly knew that React was an upgrade on my current tools. Unfortunately I couldn't just switch my work project from Angular.js to React. But I started working on side-projects and open source libraries with React. I was living two lives. Angular.js expert during the day, React padawan at night.
Eventually I decided I wanted to spend my work time working with React and got a job at PayPal working with React full-time where I was super happy.
So what was it that hooked me on React (no pun intended... hooks weren't a thing back then) so strong? Honestly, it was a few things, but if I had to summarize it to one thing it was this:
React is simple.
I didn't say "easy" because it's not easy for everyone ("easy" is relative to each individual). But it is simple. It is simpler than my former tools, and that's what hooked me.
For more on the distinction between easy and simple, watch Simplicity Matters Rich Hickey which is a fantastic talk.
The fact that React shuns mutation as an API for changing state and instead state updates are explicit function calls was a huge improvement for me. I can't tell you how much time I spent wondering what was causing my state to change incorrectly. My software was complected by the "ease" of state updates.
Yes, if you compare "two-way data binding" in Angular.js to what it takes to wire up a controlled input with React, you'll find Angular.js takes less code. And that demos incredibly well. But I've learned that what "demos" well and what is maintainable in a real-world scenario are not always correlated. React's choice to go with "one-way data flow" was a good one. It is simple, sensible, flexible, and powerful. I don't care how much code I have to write. I care about how much work it takes for me or my co-workers to change that code in the future without causing any bugs.
Using JSX syntax (aka React.createElement
syntax sugar) instead of string templates meant that I could leverage (and improve) my knowledge of the JavaScript language features rather than learning and being limited by template syntax and struggling with the global namespace/registry of Angular.js directives. I spent a lot of time trying to figure out what I messed up in my template. It's a DSL (domain-specific language) with an enormous amount of complexity.
On top of that, all the time I invested in learning that syntax is now wasted. It's completely inapplicable to anything else I work on (even if I had decided to move on to Angular 2 instead of React). However, by using JSX and understanding the basic syntax sugar, I'm able to use what I learn in non-React code all the time.
React hooks weren't available when I started using React, but React hooks is definitely another thing that makes React simple:
useState
when you need to manage state.useEffect
when you need to synchronize something outside of React with your app's state.There are certainly some things to familiarize yourself about these hooks, and there are some other hooks to help with other use cases, but these things are conceptually simple (again, not necessarily "easy").
My favorite part of hooks is how relatively easy it is to share code in a way that is also simple. To share a chunk of hooks logic between components you apply the same techniques you would when sharing non-hooks code: make a function and call it where you want to use the logic.
On top of that, it's all functions, so you can compose things together. You can combine these hooks into a single custom hook, and then you can combine other custom hooks into yet another custom hook. It's incredibly powerful and doing it is also still simple. For more on this, watch Custom Hooks in React: The Ultimate UI Abstraction Layer by Tanner Linsley.
I had great success using React to build applications used by millions of PayPal users all over the world. I love it for that scale. And what's awesome about React is that it's not limited to Facebook-scale problems. I've used it successfully to handle my small side-projects to great success. So another thing I love about React and its simplicity is how well it handles challenges, whatever the scale. I recently had a side-project I needed built fast and I was able to build the whole thing in a single index.html
file using this approach. No tooling necessary.
On top of that, React also supports really any platform with a UI. React Native, React VR, even interactive CLIs with Ink. React's simple component-based model and the power of hooks can reach anywhere. Big or small.
Once you learn React, you can build UIs anywhere.
Aside from the simplicity of the framework, another thing that I love about React is that by any metric, it's the most popular and widely used tool for building frontend applications in the world.
By a huge margin.
This kind of thing is hard to get real metrics on, but the best metric I can find to determine relative popularity is the number of users of the Developer Tools browser extension. In the Chrome DevTools, there are 2+ million users, which is twice the next most popular framework's DevTools.
However you slice it, React is extremely popular. And this has some extremely nice side-effects. In addition to React being worked on by some of the smartest engineers in the world, the size of the community means that many of the smartest engineers in the world are participating in creating and contributing to the surrounding ecosystem of libraries and tools.
This is not to suggest other frameworks don't have this (they do), but React's dominate size means that the number of people experiencing problems and solving them increases the likelihood that any problem you face has been faced and solved by someone in the community already. And if you're hiring, it's also more likely that someone is looking for a job too.
Betting on React was a big leap for me. I loved Angular.js and I built some awesome applications, libraries, and tools with it. But I'm so glad that I gave React some of my time because it's paid me back in productivity and velocity that I didn't even realize was possible before. If you'd like that in your life and you haven't jumped onboard with React, then I definitely suggest you give it a try.
And I've been working hard on something that will really help you with that 😉
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Whether you're brand new to building dynamic web applications or you've been working with React for a long time, let's contextualize the most widely used UI framework in the world: React.
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