Explanation:
An identifier is the name of a program or the names of the variables, classes, methods, namespaces or interfaces within a program that are used to identify the relevant data/info.
Typically, identifiers must start with a letter (no numbers) and must not have any spaces in them, it should indicate the meaning and usage of the element being referred and i t cannot have more than 511 characters.
An example is:
int money;
double accountBalance;
Where money and accountBalance are the identifiers.
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