LITERARY HORROR
One of the easiest methods for teenagers online to spread their stories, even if you couldn't write well, or at all – it was still accepted in the community, both story wise and general writing wise.
This, alongside the Image horror, is where some of the most iconic pop-culture figures originate from – most creepypastas originating as Images then later getting their own user-written story.
Hundreds of stories were published during this time, but I am not here to talk about books - no, I am here to talk about two ''genres'' and catagories of horror stories. Starting with the most popular one ...
What are Creepypastas?
Coming from the slang ‘ Copypasta ‘ , meaning ‘ copy and paste ‘ – Creepypastas are horror legends that are spread around the internet, little horror rumors used to scare kids - many were often spread via forums, being copypasted into chat rooms, or sent via emails ; hence the name.
These entries are user-written, paranormal stories to attempt to frighten whoever read them.
Creepypastas come in many forms, but the most popular methods were Images and Writing – and even those characters featured in the Creepypastas come in their own categories.
The Men, The Myths, the Legends

THE SLENDERMAN
The most iconic of all creepypasta and what is considered the poster child - created by Eric Knudsen back in 2006 ; Slender man, or The Slender man, as the name suggests, is a tall, thin white man with no face.
The Slenderman is characterized as this malevolent, violent entity that aims to induce fear and paranoia into people, especially kids – which he is said to abduct. Another thing that arose in popularity was the concept of ‘ Slendermans’ Mansion ‘, a place where Slenderman took abducted children – that, or where other creepypastas ( soon to be mentioned. ) stayed. Despite his origins, he was painted as a lovable, father figure to the other creepypastas - traces of malevolence nowhere to be seen.
He is not copyrighted and he is not confined to one singular piece of media, therefore, many have tried to capture this pop-icon in their own works - but nothing could ever be as culturally impacting as one Arg.

MARBLE HORNETS
Marble hornets is an ARG webseries based on the Slenderman Mythos, the first episode having been released days after the original image was uploaded.
Something most people don't know is that a majority of what is now accepted as slenderman lore came from MH, such as the pages - despite the creators stating that The Operator, the antagonist of the series, was not technically slender man - and read just based on him.
Even despite the separation from the original image and mythos, people tend to associate the characters from Marble Hornets ( Specifically Hoody and Masky ) with other creepypasta, often referred to as ‘ Proxies ‘

JEFF THE KILLER
Considered as one of the most well known creepypasta characters, known for his iconic pale white face and slit mouth smile – another poster child of the Creepypasta fandom.
Jeff the Killer greatly impacted the growth of the Creepypastas community, his existence pushing people to create their own Creepypasta - even if his writing is not very good - such as BEN DROWNED, Jane the killer, Nina the killer.
Yes, even his name was Iconic to the point where other characters were named after his likeness.
Many teens, especially young girls, admired Jeff the killer – the character, not the story. There were many accounts from now-adults who wanted to ‘’summon’’ Jeff to be with him when they were younger.
A novel published ‘ Insanity: Jeff the killer ‘ written by Neesha Nickleson being a by-product of it - infamous for its less-than-decent writing.

NINA THE KILLER
As mentioned above, Nina is one of the characters made after Jeffs likeness, having been written as one of Jeff the Killers fangirl who went insane and turned into a serial killer.
Due to the origin of her character, she is often shipped with other creepypasta character, most notably Ticci Toby, Eyeless Jack, And Jeff the Killer.

CANDLE COVE
One of the better well-written stories out there. Written by Kris Staurb, Candle Cove follows an internet forum about a fictional childrens television story of the same name.
As mentioned above, this was not written in the traditional way as most creepypastas, instead, it was written in a forum where users recount their experiences with the show; as the forum continues, the details grow more grim and disturbing -- noting a chatacter name 'Skin-taker'. The story ends with a user asking his elderly mother if she remembered Candle cove, in which she responds that whenever that 'show' was on, it was only static.

TED THE CAVER
Another one of the better-written, if not the best written creepypasta out there. Ted the Caver, written by Ted Hegemann, follows a short horror story which was self published on AngelFire presented as a diary of a man who excavates an unexplored cave with his friends.
It was shared all around the early internet, various users getting into discussions and debates on whether it was real or not. Ted Hegemann eventually came out and state that it was based on a real experience, though with some added creative liberties.
OVERVIEW
And that's just the surface level of the Creepypasta genre, there are many well-known creepypastas that I had not mentioned, just because this section would have been too long if so -- such as Eyeless jack, Jane the Killer ( both Jane Arkensaw and Jane Everlasting ), Kate the Chaser, Ticci Toby and many more. Even if they seem cringy today, Creepypastas helped kids express their creative minds and did culturally impact the internet, both negatively and positively.
There were many stories that were wonderfully written that I was not able to mention, but do think they deserve recognition.
Ted the Caver ( the original )