We pour many things down the drain to get rid of them, but some things should not be dumped down the drain because they cause build up, clogs and can damage pipes.
Fats, oils and greases are very commonly dumped down the drain. Every time you then use hot water in your sink it then heats up the grease near your sink and carries it a little ways down the drain. Eventually, this grease reaches a point where your hot water cools off, often after it gets below the foundation of your house, and it then solidifies, often along the same stretch of pipe.
Eventually this congealed mass, just like cholesterol in arteries, builds up enough that any larger matter can’t get through, and you have a rather nasty blockage. Think of it as a heart attack for your plumbing.
The simplest way to keep your plumbing arteries clear is to avoid the buildup.
Instead of sending grease, butter, or oil down the drain, pour hot oil in a tin can and when cooled place the can in the garbage. Wipe any remaining grease, butter, or oil from pans, plates, and platters with a paper towel and throw it in the garbage. This will help you keep your pipes flowing smoothly.
Learn what you can do about clogged drains http://www.plumbingguys.com/plumbing-maintenance-tips.html