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# 1.2 Variables and Data Types

#### Topic 1.2 — Variables and Data Types

**Suggested Skills:** 1.A, 2.A

**LO 1.2.A** — Identify the most appropriate data type category for a particular specification.

* **1.2.A.1** — A **data type** is a set of values and a corresponding set of operations on those values. Data types can be categorized as either primitive or reference.
* **1.2.A.2** — The primitive data types used in this course define the set of values and corresponding operations on those values for numbers and Boolean values.
* **1.2.A.3** — A **reference type** is used to define objects that are not primitive types.

**LO 1.2.B** — Develop code to declare variables to store numbers and Boolean values.

* **1.2.B.1** — The three primitive data types used in this course are `int`, `double`, and `boolean`. An `int` value is an integer. A `double` value is a real number. A `boolean` value is either `true` or `false`.
  * ❌ **EXCLUSION** — The other five primitive data types (`long`, `short`, `byte`, `float`, and `char`) are outside the scope of this course and exam.
* **1.2.B.2** — A **variable** is a storage location that holds a value, which can change while the program is running. Every variable has a name and an associated data type. A variable of a primitive type holds a primitive value from that type.


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