| Keyword | Identifier |
| System defined word | User defined words |
| Always start with lower case | Can start with any case |
| Contains only alphabetical characters | Can contain alphabets, numbers or underscore |
| Keyword | Identifier |
| System defined word | User defined words |
| Always start with lower case | Can start with any case |
| Contains only alphabetical characters | Can contain alphabets, numbers or underscore |