Variables in PHP

Variables are represented by a $ followed by the variable name. Variable names are case sensitive.

Echo variable to screen:

Print to screen:

Variable Substituion:

Variable Substituion with braces:

Recommend braces { ....... } for variables placed in string literals. Use double quotes here. Single quoted string literas will not be substituted.

Using printf()

Use printf() can be followed by one or more parameters

Concatenation

Boolean Variables (1 = true, 0 = false)

Integer Variables

Float Variables

String Variables

Constants

Once set can't be changed - no need for a dollor by convention use UPPERCASE name.

Data Casting