There are generally two broad categories of optics, magnified and non-magnified optics, with precision being the main benefit of adding either. Different technologies can be used such as a battery powered LED illuminated sights like the Trijicon SRO and MRO, or utilize fiber optics along with tritium for illumination used in their RMR or the magnified ACOG fixed power scopes. These two models also come in battery powered variants as well. Magnified Optics such as the Trijicon ACOG mentioned previously, the Eotech Vudu, Leupold Mark Series, or Sig Sauer Tango Series provide better precision at longer ranges with the latter models having variable power capability for a broader range of use and both illuminated and non illuminated options. Non-magnified optics can use a separate accessory like a magnifier to allow for higher precision on longer distances too.
Handguns are not excluded as many current models come with the ability to mount different optics whether magnified or non magnified, such as the Sig Sauer RomeoZero, Holosun 507/8/9 Series, or variable power scopes that can be found on certain large caliber pistols/revolvers for hunting.