Hi @Denv12 ,
I hope you understand my explanation.
DID is short for Dissociative Identity Disorder basically when we are little and our identity/personality is forming it is fragmented and as we get older the pieces join together in one single piece. But for some who go through trauma and abuse in childhood these fragments split off and create their own seperate identity. Not all who go through bad childhoods will develop this and most with the condition don't usually notice till mid teens/early 20s but it starts developing at a young age usually when the first occurrence of trauma happened. I have figured out that my first alter was actually with me when I was 4 I just thought she was my imaginary friend back then.
There are various kinds of DID experiences, for example I have a whole inner world with a house surrounded by forest hence the title of my book but some have full on cities in their inner world's but there are some who have no inner world or just don't remember when they front. Also alter communication varies as well with some having full communication others only have some and then a few have no communication at all. Also when I have alters front I have no idea what happens just what people around me tell me unless I am co conscious other know exactly what their alters do when out.
Anyway I gotta go but if you have more questions me or others are happy to answer