Data Types

A data type, as I'm sure you could guess from the name, is a type of data or information. When you write JUDO programs, you will be dealing with five different types of data, or data types. They are Integers, Doubles, Strings, Colors, and Booleans.

You use Integers and Doubles when you are dealing with number data. You use Strings when you are dealing with words or letter data. You use Booleans when you are dealing with truth values, and you use Colors when you are dealing with different colors.

In the below list of data types and their explanations, the word to the left of the dash (-) is the name of the data type, and the word to the left of the dash is the keyword you use when referring to that data type in a Java program. For example, in a Java program, you refer to Integers as int.

Integers - int
Used to store integer numbers. That is, positive and negative numbers without a decimal point.

    Some possible values: -1000000   -499   -12   -1   0   1   3   25   300   321431211

Doubles - double
Used to store floating-point numbers. This is, positive and negative numbers with a decimal point.

    Some possible values: -30005.3   -271.234   -3.0   -1.1   -0.321   0.0   3.14159   7202.111

Strings - String
Used to store one or more characters together. Things like words, letters, symbols, anything on a keyboard (including numbers).

    Some possible values: "Tom Dunn"   "Compaq 321"   "x"   "Ref. Id #3221"   "12:30PM"

Colors - Color
Used to store color values. Things like background color, color of paint, color of a circle.

    Some possible values: red   violet   yellow   pink   black   white

Booleans - boolean
Used to store "truth" values. Things like if checkbox is checked or not or answer to a question.

    Only possible values: true   false

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