Autocomplete functionality is probably the first use case you hear for using RxJS. Here is one possible implementation for it (code can be also found in JSBin): let input = document.querySelector(‘input’) let inputStream = Rx.Observable.fromEvent(input, ‘input’) let ul = document.querySelector(‘ul’) let responseStream = inputStream .debounceTime(500) .map(e => e.target.value) .filter(value => !value | value.length > 2)…