These odd looking contraptions are called bongs. For those of you who do not know what a bong is or how it is used, a bong is a device made to purify marijuana smoke. When the marijuana(lets just call it bud) is lit in a bowl, the person smoking it breathes in through a hole or opening, and the smoke runs through the space, into the water or whatever liquid is being used, and this purifies the smoke giving the user a better high than using a pipe or rolling bud into a paper. here is a diagram

This type of bong is really simple. there are over a million types of bongs from simpler types to complex 8 footers. here are a couple of pictures to give you an idea of what some bongs can look like. The first, third, fourth, and sixth bong are all simpler types of bongs, while the second and fifth are more complex.

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