Identifiers and Java data types

identifiers: the identifier (IDentifier) refers to a symbol used to identify an entity. There are different meanings in different application environments.
In daily life, the identifier is used to designate something, a person, to use it, his or her name; In mathematics, we often use variables or function names such as those used in programming languages, and names for variables, constants, functions, and statement blocks. ; We all call it identifiers.
Identifiers may be words, numbers, letters, symbols, or they may be made up of the above elements.

definition :

In programming languages, identifiers are words that the programmer himself prescribes, such as class names, attribute names, variable names, and so on.

Java Identifier Considerations:

1. Identifiers consist of letters, numbers, underscores "_", dollar Sign "$", and the first character cannot be a number.
2. Java keywords and reserved words cannot be identified as identifiers.
3. Identifiers do not have a length limit.
4. Identifiers are case sensitive.

Identifiers and Java data types