Java keywords or reserved words are some of the words which are used to do some internal process and other functional stuff. The reason it is reserved is that, it cannot be used flexibly as a variable or object and can only be called for its specific designated purpose. When we use it for different purpose and do the execution it will throw a compile-time error.
So java contains a list of keywords and each one has its unique functions and color based on the ide or editor.
| abstract | default | if | package | synchronized |
| assert | do | implements | private | while |
| boolean | double | import | protected | this |
| break | else | instanceof | public | volatile |
| byte | enum | int | return | throw |
| case | extends | interface | short | throws |
| catch | extends | long | switch | transient |
| continue | for | null | super | try |
| char | float | new | strictfp | void |
| class | finally | native | static |
So these are some of the actual lists of keywords used in java to keep in mind that they are already the list of reserved words and cannot be utilized elsewhere.