JSON
What is JSON?
JSON (JavaScript Object Notation) is a data interchange format that has vastly improved server-to-browser communications—especially when it comes to AJAX. It’s a language that’s similar to XML, syntactically identical to JavaScript code, and the fastest data-interchange format to be used with AJAX (Asynchronous JavaScript + XML), making it not far behind HTML when it comes to skills no front-end developer should go without.
JSON is a syntax designed to store and move data that’s sent between server and browser. It’s similar to a markup language in its syntax and how it’s used, but it’s not a markup language at its core. If you think of how XML functions in the scheme of a site—XML describes elements of data, while HTML displays that data—JSON does the same thing, just in a more streamlined way, both for the developer and the browser.
Why hire a JSON specialist?
A front-end developer who specialists in JSON can help you to create interactive, high-performance sites and apps.
JSON was the first format that allowed servers and browsers to communicate without a browser plug-in like Flash or Java. But where JSON really shines—and sets the standard—is how it functions within AJAX operations. AJAX essentially allows parts of a web page to be updated without requiring a full-page refresh, something that vastly changed the way users interact with web applications. It immediately solved problems that were caused by limited bandwidth, prevented server overload, and kept things from slowing down in the app.
AJAX was originally created in the mid-2000s with XML as its data interchange format. In that first model, after a page was loaded, new data could be called up from the server using XML as the data interchange format. JSON has improved the data retrieval process by being front-end compatible by nature with its JavaScript roots. With JSON and JSON Web Services, AJAX runs faster—it’s instantaneous and highly efficient.
JSON’s core differentiator is that it’s written in JavaScript syntax, but it’s text-only. This allows it to logically skip a front-end step: Whereas XML requires a parser to be read by a JavaScript program, JSON doesn’t require any extra software. It’s a subset of JavaScript, and so it’s compatible with the front end, right off the bat. A JavaScript program will convert JSON elements directly into JavaScript objects.
Like XML, JSON:
- Is “self-describing,” meaning humans can read it
- Uses hierarchical values
- Can be read by many programming languages
- Is able to be “fetched” by an XMLHttpRequest
How JSON is different than XML:
- Doesn’t require an end tag and won’t “break” without one
- Is shorter to read and quicker to write
- Uses arrays, which are logical ways to bulk similar data formats in an element