While constants are defined in php using the function: define () and once defined it can't be changed or undefined. I have learnedVariables are assigned when needed. They also hold numerical or text values. Using variables seems more interesting thus far. $thejourneycontinues_text.
When assigning a variable, words that come after $ sign and ending before the _ can be in any language. e.g $fetola_number=10; is still valid.
At least i can assign variables that are easy to remember. In Sesotho!
I don't see why you can't name your variables in Sesotho, but I would be wary of classifying your variables as "text" or "number". PHP doesn't require a data type when declaring a variable and PHP can actually convert data into different types, so, a variable that stared off holding an int may become a float or even string of letters.
crh(); function takes a number and returns it's corresponding ascii character as a letter or another number
ord(); function takes a letter and returns it's ascii code
Even chess pieces can be displayed in the browser using ascii codes.
I know the chess pieces are not directly related to PHP but I think they're pretty cool.