The "wake up" meme started as a creepypasta that has become a meme involving seemingly normal and generally positive sentences that suddenly write "wake up" in larger lettering.

It is unknown where this meme originated but one could assume that it was created for a creepypasta site and adapted on sites such as tumblr, facebook etc.

There are many similar texts that follow the same theme, but this is one of the original texts:
It has been reported that some victims of torture, during the act, would retreat into a fantasy world from which they could not wake up. In this catatonic state, the victim lived in a world just like their normal one, except they weren’t being tortured. The only way that they realized they needed to wake up was a note they found in their fantasy world. It would tell them about their condition, and tell them to wake up. Even then, it would often take months until they were ready to discard their fantasy world and please wake up.

this version of the text cannot be called the 'original' as stories similar to this have been around for a long time and the true original seems to be buried in the old corners of the internet.

other adaptations apply for their respective websites, such as the tumblr version that is about rape, the facebook version about a coma and various other unfortunate predicaments.

the meme itself can involve anything from long texts that slowly start to give readers an uneasy feeling by saying "wake up" in increasing frequency, to short jokes that put a little too much emphasis on the "wake up".

the optimal "wake up" meme will include no reference to rape, comas, or torture and will seem to appear out of nowhere, barely noticed by the viewer.

Please, wake up.