If you came here, and your gallery works, but you’re still hungry for knowledge, I’ve got a little treat for you. You can open StackBlitz go to Photo Component and look at a bunch of code in
ngAfterViewInit method. It’s a sketch of a new feature: adding description to photo and saving it, for example, in Local Storage. There is "saving" indicator here. It can be seen when user who is writing description becomes idle for a bit, or leaves input. You can meditate on this code, try to have some fun with combining events, debouncing them, delaying and lot more. Dig into documentation and check what new operators mean. I’m sure Observables will reveal their beauty to you, through this piece of code.