One of the most widely used and well-known absolute dating techniques is carbon-14 (or radiocarbon) dating, which is used to date organic remains.
Relative age allows scientists to know whether something is older or younger than something else, while absolute age means that scientists know the exact number in years that have passed since the object was created.
There are absolute ages and there are relative ages. We use a variety of laboratory techniques to figure out absolute ages of rocks, often having to do with the known rates of decay of radioactive elements into detectable daughter products.
Unfortunately, those methods don't work on all rocks, and they don't work at all if you don't have rocks in the laboratory to age-date. They are descriptions of how one rock or event is older or younger than another.
Absolute age is more straight-forward and does not require any other objects for comparison.
Absolute dating is the process of determining an age on a specified chronology in archaeology and geology.