Holla is a slang word that is often used in informal conversations. The word ‘Holla’ is derived from the word ‘Holler’ that means to shout or to cry. Holla is also often used by Chavs and trap stars. It is used to attract attention and is a way to express goodbye like “I will holla at you later” means “I will meet you later, goodbye for now”. People think it cool when they say ‘Holla’ and it is one of the most popular trends in present times.