YJ (87-95) Square head lights, leaf springs, minimal interior, 2.5L, 4.2L or 4.0L engine options
TJ (97-06) Round head lights, coil springs, more car like interior, 2.5L, 2.4L, or 4.0L engine options, can also come in a Rubicon
JK (07-now) Round head lights, plastic grill, coil springs, car like interior, 3.8L or 3.6L V6 engine options, can also come in a Rubicon, available in a 4 door, much larger than a YJ or TJ.
JL (2017-???) Newest Jeep, will have round headlights and be available in a 4 door. Should be similar in size to a JK.
The newer you get the more comfortable they get on road and more capable they get off road in stock form. The older they are the cheaper and easier they are to modify and the YJ and TJ are smaller so are easier to maneuver off road.
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