Glass is the material most commonly used when smoking marijuana out of a pipe. Glass pipes can vary in color and size and can be decorated with unique designs and patterns. Glass pipes can cost quite a lot of money and sometimes break easily, but are considered much more desirable than metal pipes, which can get uncomfortably hot and give extremely harsh hits, or wooden pipes, which will not last as long and can get permanently stained with an unpleasant flavor. The term "glass" can also sometimes be synonymous with the word "pipe" or "piece." Example Usage: "Where's your glass pipe, man? I told you this haze will be way better if you ditch that old metal thing. Come on, you know you'll hold the glass one steady. The hits will be so much smoother." "Nice glass dude, is that custom made?" "Every year on my birthday, I treat myself to some new glass. Last year I bought a bong, so this year I'm going to buy a bubbler."