Optic is usually a 1x red dot type of thing for me, but it COULD be a scope for some people… Many people use a variable 1-4x or 1-6x “scope” on their defensive rifles. If using a scope for that, the reticle usually glows (so it can be used at night too).
The term “scope” usually means a magnified optic. “Optic” is the term for any type of visual aid on a rifle, though… (Or, sometimes a pistol - red dots are gaining in popularity on pistols now)
I personally am not a fan of magnified optics, though. I like 1x optics on a defensive rifle more.
As stated about - I like the AImpoint Micro or the Mepro 21. There is no magnification. But, the Aimpoint uses a red dot. The Mepro 21 I have uses a triangle. Instead of using iron sights, this is easier to use and faster. Plus, you can use it in the dark. Just cover the target with the dot or the triangle, and that’s where ya hit.
I like the triangle on the Mepro 21- because you can use the tip for accurate shots. And for fast shots, you just cover the target with the triangle.
Many of the red dots have to be turned on and off because of battery. So, if ya grab the rifle quickly, ya gotta remember to turn the optic on. I like the Aimpoint because you can leave it on, and the battery lasts about 5 years. You never have to turn it off… And, if you are worried about the battery, just swap it out maybe at the 3 year mark…
And, the Mepro 21 is always on too. It has no electronics. The tritium inside will not work as well after about 10 years, though. But, even after the tritium dies, the optic will still work 100% in daylight (it uses fiber optics to gather the light). Many people have reported that the Mepro is still barely visible in the dark even at 15 years, though.
Optics like these are much, much faster than iron sights, and you can use them in light situations that you would not be able to see the iron sights.