When developing applications in Java, one of the most essential starting points is understanding the basic vocabulary of the language. Among the core elements that make up this vocabulary are what we call keywords.
In Java, keywords are reserved words that have predefined meanings within the language. These words are part of the Java syntax and serve specific roles in defining the structure and behavior of a program.
Because they are reserved, you cannot use keywords as names for variables, methods, classes, or any other identifiers in your code. Doing so will result in a compilation error.
Java currently defines 51 keywords, each serving a specific purpose in language syntax, flow control, memory management, and object-oriented structure. The table below lists all the reserved keywords in Java:
No. As you progress in Java development, you will naturally become familiar with many of these keywords through usage and context. Others can easily be looked up as needed. However, it's important to understand that these keywords are reserved by the language and cannot be repurposed for naming custom variables, methods, or classes.