Perso-Arabic script is a way of writing that is used in many languages like Arabic, Persian, Urdu, and Hindi. It uses a special set of symbols called "letters" that make different sounds when we say them out loud.
Think of these letters like the building blocks of words - just like how you put different Lego blocks together to make a cool toy, we put different letters together to make words.
Perso-Arabic script is special because the letters are written from right to left instead of left to right like in English. It also has some letters that look similar to each other but make different sounds, and other letters that look different but make the same sound.
To help people read and write, they use something called diacritic marks, which are little dots, lines, or squiggles placed above or below the letters. These marks tell us how to pronounce the words correctly.
In many countries where Perso-Arabic script is used, people learn it in school to be able to read and write their own language. It's an important way of communicating and expressing themselves, just like how you might use drawing or writing in English!