Thus: the people of the Right (the people of happiness and prosperity, who receive their Records in their right hands): how happy and prosperous are the people of the Right
So, (firstly) the blessed ones. Oh, how wonderful are the blessed ones! ('Yumn' = Blessing = Bliss = Grace = Right side = Right action (19:52), (28:30), (56:27))
So those on the Right Hand (i.e. those who will be given their Records in their right hands), Who will be those on the Right Hand? (As a respect for them, because they will enter Paradise)
The people of the right (the fortunate-happy ones who have attained the Truth) – and what people of the right?
Al-muntakhab fi tafsir al-Qur'an al-Karim
A position on the right side which of right belongs to those who had dearly earned the position on the right; their works agreed with the Divine standard of actions and conduct and their hearts had been impressed with the image of piety. These, has Allah destined to win their way to paradise