from

signature: from(ish: ObservableInput, mapFn: function, thisArg: any, scheduler: Scheduler): Observable

This operator can also be used to emit a string as a sequence of
characters!

Example 1: Observable from array

Example 2: Observable from promise

( jsBin |
)

Example 3: Observable from collection

Example 4: Observable from string

( jsBin |
)

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