Arabic has 3 main short vowels also called ‘harakat’.
These harakat are:
a short line above the letter
a short line under the letter
a small waw above the letter
The 3 main short vowels are shortened versions of the long letters: ا alif, ي ya, and و waw.
Listen to Mu’alima Bushra say these vowels in the next video.
In many children’s books you will find most of the words with their harakat on the letters as young readers are still learning how to read. The Holy Quran also has full harakat on all the words to preserve the meaning of the Holy Book.
In most other reading sources (articles, news, blogs, books) you will not find harakat on every letter. As you listen and read Arabic you will find that practice and lots of exposure to the language will have you naturally reading the words with or without the presence of harakat.