Timeline

The term timeline specifically refers to a 4D structure within the multiverse.

Anchorange 15C
Most of the time travellers of TTN are centred around this timeline, and it's used as a homebase for some.

Fiction Timeline
Nicknamed as such, as it was created by Chocer who wished to replicate story tropes in a real environment. Its residents include medieval knights, samurai, hat tipping cowboys, magical princesses, and vikings - all of course in the same time period. Those who originate from it typically seem like characters ripped straight from a fictional universe - which isn't incorrect, considering that was the intent.