harakat

In the Arabic script, (حركات — the singular is حركة) are the diacritic marks used to represent vowel sounds. The literal meaning of is "movements", e.g. in the context of moving air waves that we produce while pronouncing vowels. The Arabic script is an Impure abjad rather than an alphabet, meaning that all the consonant sounds are represented by letters but short vowel sounds are often not represented in writing. The are optional symbols that can be used to represent all the vowels that are not indicated in the ordinary spelling.
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