This is the Sharp Phototriac. It can often be rather complicated to turn on AC sources with logic. Sure you can use a relay but the switching speed is slow and a coil usually requires a lot of current. This is why a phototriac can often be a good way to go.

Just apply a controlled DC current to the +/- pins (approximately 20mA @ 1.2V) and the phototriac will engage allowing AC current to flow. Remove the DC voltage and the the triac will stop passing AC current. The two pins with the sine wave above them are the AC pins.

This triac is rated for 8A @ 250VAC for the AC pins (may require heatsinking as you approach 8A). These are the same components that I used to build my bluetooth light switch: https://www.youtube.com/watch?v=o4gIVux39iQ

I used these with an Attiny85 https://www.tindie.com/products/Hanscorp2014/attiny85/ and they worked great!