JavaDoc is a tool and documentation format in Java used for generating API documentation in a standardized and readable format. It is an essential part of Java development, allowing developers to document their code and produce documentation that is easily accessible and understandable by other developers. Here are key aspects of JavaDoc:

1. Documentation Comments: JavaDoc uses specially formatted comments within Java source code to document classes, interfaces, methods, fields, and other elements. These comments begin with /** and end with */.

2. Tags: JavaDoc comments include tags that provide structured information about code elements. Common tags include @param (for method parameters), @return (for method return values), @throws (for exceptions thrown by a method), and @see (for cross-referencing other classes or methods).

3. Generating Documentation: To generate JavaDoc documentation, you can use the javadoc tool provided with the Java Development Kit (JDK). Running javadoc on your source code will process the JavaDoc comments and create HTML documentation files.

4. HTML Documentation: The output of the JavaDoc tool is typically a set of HTML files that include documentation for classes, methods, and other code elements. These HTML files can be viewed in a web browser, making it easy for developers to access documentation.

5. Standardized Format: JavaDoc follows a standardized format and style, making it consistent and familiar to developers across different Java projects. This consistency helps improve code readability and maintainability.

Here’s an example of a JavaDoc comment for a method:

In this example, the JavaDoc comment provides a description of the method’s purpose and usage, documents the parameters (a and b), and specifies the return value. When you run the javadoc tool on this code, it will generate HTML documentation that includes this information.