Welcome to ReactiveX!

Markdown table:

	single items	mulitple items
synchronous	`T getData()`	`Iterable<T> getData()`
asynchronous	`Future<T> getData()`	`Observable<T> getData()`

HTML table:

	single items	multiple items
Observables fill the gap by being the ideal implementation of access to asynchronous sequences of multiple items
synchronous	`T getData()`	`Iterable<T> getData()`
asynchronous	`Future<T> getData()`	`Observable<T> getData()`

Example code showing how similar high-order functions can be applied to an Iterable and an Observable

Iterable Observable

Example code showing how similar high-order functions can be applied to an Iterable and an Observable
`getDataFromLocalMemory() .skip(10) .take(5) .map({ s -> return s + " transformed" }) .forEach({ println "next => " + it })`	`getDataFromNetwork() .skip(10) .take(5) .map({ s -> return s + " transformed" }) .subscribe({ println "onNext => " + it })`

getDataFromLocalMemory()
.skip(10)
.take(5)
.map({ s -> return s + " transformed" })
.forEach({ println "next => " + it })

getDataFromNetwork()
.skip(10)
.take(5)
.map({ s -> return s + " transformed" })
.subscribe({ println "onNext => " + it })

Code snippet:

def print_hi(name)
  puts "Hi, #{name}"
end
print_hi('Tom')
#=> prints 'Hi, Tom' to STDOUT.