Constants are variables that do not change in value durign a script. You can use the define tool in order to assign a value to a constant.
This was written using the echo command followed by the constant name, exampleYou can also use the command const in order to create a variable. The difference is that const is case senstive while define is not. For example, the define variable: example can be spelled with different cap, but, the const variable: ExampLe needs to capital E and L in order for it to work.
This was written using echo and the const case sensitive variable.