There are certain things that you shouldn't put down your sink. It's true there are certain things that go down your drain and it has to be that way, but you can keep it cleaned out. If you don't keep it cleaned out it will become clogged up. Sink and line maintenance is a part of being a home owner. It's good to review the basics, and learn about what some people purposely allow into their sinks and lines.
Read this list about the don'ts of rinsing the wrong thing, and not keeping a drain clean.
Food. Don't rinse foods down you sink unless you have a garbage disposal, it'll stop it up. This includes things such as pop corn kernels, peelings from any vegetable or fruit, pasta shells, breads or butters. All of these can form a plug between your sink and line for drainage to the outside. Breads and butters are really bad about clogging up a line because it forms a gooey mixture, and clings to the sides and bottom of the line.
Grease. It doesn't matter what type of grease it is. Nor does it matter if it's hot or cold grease. Hot grease won't clean a line nor run any faster down a drain. It clings to the sides of it and forms a hard plug. It thickens very fast when exposed to the cooler lines beneath your sink. Always dispose of grease after it's cooled in an air tight container either in the refrigerator or left on a counter top. Dispose of your grease into the garbage after it's cooled.
Detergents. Using a dish washing liquid that's made for sink usage is the only thing you should put down your sink. Other types of detergents made for car washing or even for the dishwasher will clog it up, especially if you use in abundance. It seems logical that you'd be able to use a dishwasher liquid in the sink. However the force of the dishwashers agitating action breaks apart the thicker detergent where you just rinsing it down the drain will not. The same applies for a clothes washer too. The detergent itself is exposed to the agitating and breaks down.
Pesticides. Never pour toxic pesticides down your sink. They can when mixed with water congeal, and form hard cores in the sink line. Besides it eats out the lines and causes leaks to occur. Dispose of them properly.
Calcium Chlorate and Lime. Some people that are on septic systems have poured excessive amounts of calcium chlorate down a sink line drain to get rid of odor. It's true some products consist of these substances, but they are specially formulated for sink usage. Bags of calcium chlorate and lime will cause a plug not only to develop at the sink goose neck, but farther down the line too. When calcium chlorate gets wet it turns to cement and hardens. Never pour the powered form down you sink lines because it will break off down the line and cause a secondary plug.
Outside Oils. As with grease from the kitchen never allow mechanical or cleaning oils down your sink. Outside cleaning oils have a strong petroleum based formulation. Lubricating oils for joints or hinges, and motor oil are two of the tops on the list. People have poured this down their sinks, and had horrible plugs in the drain sink lines. You need to know that it's against the EPA, Environmental Protection Agency to pour motor oil in anything besides a designated container for it. You could get into huge legal and financial trouble if any traces of it show up in a water contamination test. It's not worth the risk, and it's bad for the environment too.
Inside Oils. Your lines won't appreciated having baby oils, liquid eye liners, bottles of very oily based moisturizing oils, and hunks of oil based soaps shoved down its drain lines. Dispose of them properly by leaving them in the container, or poured into another container if you want to reuse the bottles. Pick out the soap and throw away in the garbage too.
Hair is another thing that will stop up your drain. Use a hair trap on all drains so it won't stop up your lines. Also conduct a monthly hair sweep, and clean out all drains in the house, and that does include your kitchen drain too. Every month or so pour a reliable drain cleaner down your lines, so there won't be any more plugged drains to fight with