Ranged builds are defined by skill gems that use range abilities and typically play from a greater distance. Survivability of these builds is better as we are not up close as melee, but we do mostly rely on avoiding damage.
Ranged skills in Path of Exile are, for example, Spark, Explosive Concoction, Explosive Arrow or Storm Brand to name a few. These skills will put you out of the range of monsters. Ranged builds are usually easier for new players to start with as you will have more overview of your surroundings than a typical melee build.
So ranged builds typically play from a greater distance and do not have to handle getting in the thick of monsters. Survivability for these builds relies mostly on avoiding damage and are easier to play for new players. Builds that have the Ranged tag are build that will do just that