AP Comp Sci Principles Unit 4.

Expression

Expression

a combination of operators and values that evaluates to a single value

Variable

holds one value at a time

a reference to a value or expression that can be used repeatedly throughout a program

Assignment Operator

allows a program to change the value represented by a variable

Debugging

the process of finding and fixing problems in code

Global Variables

Permanent. Can be used anywhere in your code

var used outside an onEvent()

Local Variables

Temporary. Can be used only in the part of the code where it was created, like inside an onEvent(). Deleted once the onEvent() is done running

var used inside an onEvent()

Numbers

Strings

Boolean

made of digits 0-9; no quotes

made of any characters; inside double quotes

true or false

Boolean Value

a data type that is either true or false

Comparison Operators

indicate a boolean expression

Function

a named group of programming instructions. Also referred to as a “procedure”

Function call

a command that executes the code within a function