JSON Schema is a powerful standard used to describe the structure and validation rules of JSON (JavaScript Object Notation) data. It enables developers to define the shape, type, and constraints of JSON objects, making it essential for validating and enforcing consistency in data exchange between systems.

Core Components
1. Types: Defines the data type for properties, such as string, number, array, object, or boolean.
2. Validation Rules: Specifies constraints like required fields, minimum and maximum values, and string patterns.
3. Hierarchical Structures: Supports nesting and recursive definitions, enabling complex data modeling.
4. Extensibility: Allows defining reusable schema components through $ref, promoting modularity.

Use Cases
- API Development: Ensures data sent and received conforms to expected formats, improving API reliability.
- Data Validation: Automatically checks incoming data in applications for correctness.
- Configuration Management: Validates configuration files in JSON format for applications and tools.

Advantages
- Reduces errors in data communication by enforcing strict validation.
- Enhances documentation and understanding of data structures.
- Promotes compatibility and interoperability in distributed systems.

JSON Schema is widely used in modern application development, especially in RESTful APIs and microservices architectures.