What are functional principles?

Functional principles are like the rules that help things work smoothly and predictably, just like how your favorite toy works every time you play with it.

Imagine you have a magic box (we'll call it a function) that takes in something, does a little job on it, and gives you back something else. That’s what functional principles are all about: making sure the inputs go through clear steps to get the right outputs, like how your toy always makes noise when you press its button.

Let's say your toy has a red button. When you press it, it lights up and plays music. That’s like a function:

• You press the button (input),
• The toy lights up and plays music (output).

Every time you do this, the same thing happens, that’s what makes your toy fun and easy to use.

If your toy had no rules, like sometimes it played music and sometimes it just turned off, it wouldn’t be as fun. Functional principles are like those rules that help things stay consistent and reliable.