JSON vs. XML

When two computers talk to each other over the internet, they need a structured way to send data. The two biggest standards are JSON (JavaScript Object Notation) and XML (Extensible Markup Language).

Visual Comparison

{
  "user": {
    "id": 101,
    "name": "Alice"
  }
}
    

<user>
  <id>101</id>
  <name>Alice</name>
</user>
    

JSON: The Modern Standard

JSON was born out of JavaScript, but it is now language-independent.

Pros:

• Lightweight: Less typing. Notice how XML requires </name> to close the tag? JSON just uses }, saving bytes.
• Native: In web browsers, JSON parses instantly into usable objects.
• Readable: It looks like a standard list or dictionary.

Cons:

• No Comments: You cannot strictly write comments in standard JSON.
• Data Types: Limited to Strings, Numbers, Booleans, Null, Arrays, and Objects. No dates (dates are just strings).

XML: The Enterprise Heavyweight

XML looks like HTML. It is very strict and verbose.

Pros:

• Metadata: You can add attributes to tags: <price currency="USD">50</price>.
• Validation: XML has schemas (XSD) that strictly enforce rules (e.g., "The ID field MUST be an integer"). This is crucial for banking and medical software.
• Comments: You can use <!-- comments -->.

Which one wins?

In 90% of web development today (APIs, mobile apps), JSON wins because it is smaller and faster to parse. XML is still king in complex enterprise systems, document storage (like Microsoft Word .docx files), and configuration files.