The delay effect is widely used in electronic music and lot of other genres as well. It’s a great way to add depth, density or an ethereal quality to synth lines, pads, vocals or any other sound really.
I use delay a lot in my own productions to add that extra atmosphere to otherwise dull sounds.
Here’s a quick introduction on how a simple delay can affect the sound. The FX unit in this tutorial video is Fruity Delay 2, one of the easiest and handiest digital delay units.