The Arabic name Tajweed linguistically indicates 'proficiency' or 'doing something well'.
It comes from the same source letters as the word Jayyid, which means 'good'. When connected to the Quran, it means giving every letter of the Quran its rights and dues of characteristics when we recite the Quran and observing the commands that apply to those letters in different situations.
We give the words their rights by following the essential features of each letter. We give them their dues by observing the characteristics of each letter that are present in them some of the time and not present at other times.
The Quran was revealed with Tajweed rules applied to it. In other words, when the angel Jibreel (Gabriel), may Allah exalt his mention, recited the words of Allah to the Prophet Muhammad Sallallahu `Alayhi Wa Sallam ( may Allah exalt his mention ) he recited them in a certain way and he showed the Prophet sallallaahu `alayhi wa sallam ( may Allah exalt his mention ) the ways in which it was permissible to recite the Quran.
So it is necessary upon us to follow those rules so that we recite it in the way it was revealed.
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