>>7
The drawback for LS is that it is TTL and so has humongous power consumption, it was the mainstream logic family until CMOS was introduced in the HC family.
Fucking around with these things that have 4 logic gates each is a waste of time unless you're going for some sort of 4-bit computer construction renaissance, get a lolduino or a 5 buck mcu kit instead and make something interesting like a dongbot.