Java has very strong conventions for names. You are expected to follow these conventions.

Please note that this is not just a class requirement, but an expectation in the "real world." You may find different conventions in some very early Java books, but the following conventions are now almost universally followed.

Classes and Interfaces

• The names of classes and interfaces always begin with a capital letter.
• If the name consists of a single word, the rest of the name is in lowercase.
• If the name consists of multiple words, the first letter of each word is capitalized.
• Examples:
  Object, Button, TextArea, ActionListener, ActionApapter, EOFException.

Fields (that is, variables) and methods

• The names of fields and methods always begin with a lowercase letter.
• If the name consists of a single word, it is entirely in lowercase.
• If the name consists of multiple words, the first letter of each word (after the first) is capitalized.
• Examples:
  println, equals, getParameter, addActionListener, out, height, maxArraySize.

Constants (variables that are declared final)

• The names of constants are fully capitalized.
• If the name consists of multiple words, the words are separated by underscores.
• Examples:
  E, PI, MAX_VALUE, EAST, CURRENCY_SYMBOL.
• Exception: The names of Colors are all lowercase (red, yellow, green, blue, etc.) These were defined before the naming conventions became firmly established.

Additional (less strong) conventions

• i, j, k are used as the indices of for loops.
• Abbreviations are less commonly used in Java than in other languages. This may be because, unlike C, Pascal, FORTRAN, and other common languages, all characters are significant. Thus you have getParameter instead of getParm. Very common abbreviations, such as max and min, are still used.