I am a fan of the Midland radios myself, though there are many good brands out there.
Most 2-way radios today are dual frequency radios. Meaning they are capable of both FRS & GRMS channels. FRS channels are your free local channels, where GRMS channels require a license to broadcast on. FRS channels are a lower power & GRMS are high power channels. The range on FRS transmission is usually less than a mile. Range on GRMS channels is usually 1-2 miles.
There are also privacy codes (CTCSS & DCS) that allow you, or your group, to broadcast on a specific area of any given channel. This helps cut down on interference in crowded areas, giving you better odds of being the only group on that channel & privacy code.