It's pretty simple, 2 way means that its built with 2 speakers in it or rather 1 speaker built into another (tweeter). for example, say its a 6x9 2 way speaker. you will actually have the main speake wihich is 6x9 in size and in the middle you will have a little speaker a.k.a. tweeter hence the name 2 way cause the sound is coming out 2 ways. same way with the 3-way, having the main speaker and 2 little tweeters built in/on.