These operators allow the creation of an observable from nearly anything. From generic to specific use-cases you are free, and encouraged, to turn everything into a stream.
ajax ⭐
create
defer
empty
from ⭐
fromEvent
generate
interval
of ⭐
range
throw
timer
⭐ - commonly used
Creating Observables From Scratch
🎥 💵 - André Staltz