The buffer() and window() operators batch up emissions into collections or Observables based on a defined scope, which regularly consolidates rather than omits emissions.The throttle() operator, however, omits emissions when they occur rapidly. This is helpful when rapid emissions are assumed to be redundant or unwanted, such as a user clicking on a button repeatedly. For these situations, you can use the throttleLast(), throttleFirst(), and throttleWithTimeout() operators to only let the first or last element in a rapid sequence of emissions through. How you choose one of the many rapid emissions is determined by your choice of operator, parameters, and arguments.
For the examples in this section, we are going to work with this case: we have three Observable.interval() sources, the first emitting every 100 milliseconds, the second every 300 milliseconds...