What is the difference between a primitive data type and an object in programming?

Primitive data types are basic types that contain a single value and have no methods or properties that change their state. In Java, primitives include int, double, boolean, etc. They are stored on the stack and have a fixed size.

Objects are complex data structures that can contain multiple values and methods. They are stored on the heap, and variables hold references to objects.

Main differences:

• Primitives store values directly, objects store references.
• Primitives are immutable, objects can be mutable.
• Primitives do not have methods (although wrapper classes do), objects have methods and fields.

Example:

int a = 5; // primitive
String s = "hello"; // object

// To change primitive value, assign a new one
// To change object, use methods
s = s.toUpperCase();