Today I'll be talking about Shaytaan. (Plural of Shaytaan; Shayatin). Before we start here is a question that is very confusing for people.
Q: Difference between Shayatin and devils is?
A: The difference is that devils are mortal as Shayatin are immortal as they die when their leader, Iblees dies. Iblees dies on Yaum-ul-Qiyaam and thus they are immortal till the last day.
Anyway, now let's talk about how Iblees became Iblees.
Here is Iblees's story:
Long ago, before people were created, there was only Allah (SWT), devils, angels and e.t.c. Scholars say that Iblees at that time was called Azazil . He was living in the heavens, but one day him and the angels saw Adaam (AS), a human. After a while, he sneezed and that is how he came to life. Adaam (AS) was made out of clay, mud e.t.c just like all humans. Allah (SWT) then ordered all the angels to bow down to him. Azazil didn't because he said he was made of fire and that he was more superior than Adaam (AS). Allah (SWT) got angry with him and banished him from heaven. Allah (SWT) called him Iblees or Shaytaan and said "You will now go to Jahannam no matter what. (hellfire, Jahannam). He (SWT) told Iblees that he could try to take people with him to Jahannam. So he did. That's why Iblees tries to make people do bad things, so they can go to Jahannam with him.
Iblees has lots of helpers that try to take people to Jahannam too. They are also like him, arrogant, lead astray, ugly e.t.c. We should always be careful of what we do because Iblees and the Shayatin will always try to trick us into going to Jahannam.
Here is a video by MercifulServant about how Azazil became Iblees: