Yes. At least that’s the way my Pixel phone works.
If you use the square button to select one of those “open” programs, you’ll likely find that it wasn’t really open. its final state was just saved to speed up the reloading process.
Word of advise regarding Moto: If you shake the phone to turn on the flashlight, do not also use the same method to turn off the alarm. Damn near blinded myself trying to turn the alarm off this morning. 
Thank you. So the programs are actually closed and this is just a quick way to reopen them.
On Android Nougat or newer, it’s also how you can do a split screen.
My sons and I all have these phones and they are indeed great for the money. We bought them off Amazon for about $160 each I think it was.
I got a LG G7 2-for-1 deal, which replaced a LG V30 that broke after a drop and T-Mobile wouldn’t cover. I liked the display of the V30 better, and didn’t care for the “notch” at the top on the G7, however I found an app that pretty much hides it by keeping the top notification area background black. It’s a pretty good phone, LOVE the camera. Everything else is pretty much a standard Android experience, which is more than I can say for Samsungs (way too much bloatware). I’ve had a few Samsungs, I like them okay, their AMOLED displays are pretty vibrant and if that’s your most important criteria, I’d probably do that, even though they’re going to be a bit more expensive. LG seems to be becoming pretty good competition to them though.