 The JSON or XML basically used in their programming languages because of simplicity and structured data format. In many ways, you can think of JSON as an alternative to XML, at least in terms of web application and nowadays for web API also. The Ajax concept originally used XML to transmit data between server and browser. But in recent years, JSON has become a more popular way to carry Ajax data. JSON and XML both have well documented open standards on the web and both are human and machine readable. Just a few years ago, XML was the only choice for open data interchange. But developments in open data sharing have introduced more options for developers each with their own set of benefits. As you can see here that XML looks more verbose in comparing with JSON while JSON has a more compact style than XML. The lightweight approach of JSON make significant improvements in restful APIs while working with complex systems. Now there is something that may consider a problem with XML and that is that you can represent the same data in multiple different ways and JSON is a lot simpler than XML. As we can see here that there are multiple ways to represent data in XML and XML can vary verbose. But above all of this, there is one fundamental difference between XML and JSON is that XML is a markup language whereas JSON is a way of representing objects. Now let's discuss some of the more difference between the JSON and XML. So JSON looks more like the data structure as we declare in programming languages but most importantly of all it has a defined way of distinguishing between a record and a list. An object notation is practically useless without such distinction and XML has no such distinction. Look at this XML example. Here patient is a record and phone number is a list but they are not identified as such by the syntax. The advantage of JSON is that the low level syntax has that distinction built into it. So it's very succinct and universal. Okay, and XML can separate data from metadata via the use of elements and attributes while JSON does not have such a concept. Another key difference is the addressing of values. JSON has objects with a simple key to value mapping whereas in XML addressing happens on nodes. And next the most significant advantage that JSON has over XML is that JSON is a subset of JavaScript. So code to parse and package it fits very naturally into JavaScript code. Another one is XML tag names cannot contain any of the characters like this. It even not also contains a space character whereas JSON keys or name can contain these characters. Okay, and XML is document oriented while JSON is data oriented. JSON can be mapped more easily to object oriented systems. Next is XML is being widely adopted by the computer industry but JSON's simplicity and the ease of converting from XML to JSON makes JSON ultimately more adoptable. Alright, building a restful APIs just like our PDF.co API requires a reliable, fast and easy to use form of data exchange. All of the PDF.co APIs uses JSON which we have already seen in previous modules video. As restful API practices and simpler forms of data exchange become more popular, JSON will be leaving XML practices in that test.