tutorial 2: introduction to programming elements: values, variables, and operators

Notes

• values can be literal or variable
• there are different types of variables, both different types of numeric variables as well as text variables that are called string variables.
• The assignment operator in JavaScript is the equal sign (=)
• the arithmatic operators + - * / in JavaScript function as they do in typical mathematical equations
• A value is the discreet data used in a calculation. In order for programs to run, values must be assigned.
• Commonly, variables are used as containers for data, placeholders that help define how a calculation will operate without having to know the exact values being used.

Definitions

literal values

discreet numbers or text that can be used in a program

variable

containter for storing values. Variables must be declared to be used.

validation

validation of variables refers to checking the type or format to ensure it is usable before attempting to use a variable in a program.

expression

values and operators with a result; expressions in JavaScript are governed by usual arithmatical rules (they are like regular math)

operators

symbols used in expressions that convey specific mathematical meaning

JavaScript Syntax Example

Declaring variables

var x = 8;

var y = 4.53454;

var z;

Expression with an operator

z = x + y;