Allah is the name God Almighty has given Himself as is mentioned many times in the Holy Quran.
Qu'ran, Chapter 112, Verses 1 - 4
Muslims believe He has no partners in divinity, which includes having no son, and nothing in the universe is similar to Him. Muslims believe that Allah is the Originator and Sustainer of the universe and that he created human beings for only one purpose: to worship Him alone.
To worship anything besides Allah is considered a grave sin. The reward for worshiping Him alone and following his path is goodness in this world and Paradise in the next .
Qur'an, Chapter 22, Verse 23
The first pillar of iman (faith) in Islam is Belief in Allah. As Muslims, we believe in Allah in accordance with His beautiful names and attributes. Allah has revealed His names repeatedly in the Holy Quran primarily for us to understand who He is. Learning and memorizing the names of Allah will help us to identify the correct way to believe in Him. There is nothing more sacred and blessed than understanding the names of Allah and living by them. How do we expect to worship, love, fear and trust our Lord, The Almighty Allah, if we don’t know who He is?
Allah says in the Quran:
"And to Allah belong the best names, so invoke Him by them" (Quran 7:180)
"Allah – there is no deity except Him. To Him belong the best names". (Quran 20:8)
"He is Allah, the Creator, the Inventor, the Fashioner; to Him belong the best names". (Quran 59:24)
Prophet Muhammad (ﷺ) said, “Allah has ninety-nine names, i.e. one-hundred minus one, and whoever knows them will go to Paradise.”
Abu Huraira reported Allah’s Messenger (ﷺ) as saying: "There are ninety-nine names of Allah; he who commits them to memory would get into Paradise. Verily, Allah is Odd (He is one, and it is an odd number) and He loves odd number..”