Identifiers are indeed the <em>identifiers of variables, functions, classes, packages, or interfaces.</em> These are not the objects themselves, as contrasted to literals, but rather means of alluding to things, and the further calculation can be defined as follows:
legal and conventional:
The class identification whose names starting with just an uppercase letter includes no space.
It <em>stresses each subsequent word</em> with an uppercase letter that falls within<em> legal</em><em> and </em><em>customary</em>.
The example are "<u>association Rules(), getReady(), and displayTotal()</u>".
legal but unconventional:
The class identification whose new words do not begin with <u>initial uppercase letters, utilizing underscore</u>.
It marks the whole letter with uppercase, and commencing the first letter with lowercase is regarded as legal but unusual.
The example are "<u>PayrollApp(), Accounts_Receivable()</u>".
illegal:
Class IDs with a space between two words, reserved keywords, names that begin with numbers, and <u>symbols (except $,_) </u>are prohibited.
The example are "<u>void(), Golden Retriever(), invoice#(), 36542ZipCode() and 911()</u>".