Variables are, by the author's convention, always in UPPER CASE CHARACTERS. This makes them easier to recognize.
Variables are assigned a value(s) using an assignment operation:
VARIABLE=stringNote that there are NO spaces before and after the equal (=) sign: this is essential, otherwise the shell would interpret those spaces.
The content of the variable is represented by prefixing the variable with
a dollar sign ($).
For example, $FRUIT means the content of variable FRUIT.