The sink is may be thee most important thing in the kitchen, in it you wash the food before prepare the meal, dishes and everything you need to cook, eat or need to be cleaned up. Therefore is of major importance to choose the right one. You will be surprised how much types and materials there are on the market.
May be the first thing you have to figure out is the size of the sink. It depends of size of the room and how much space you can make for it. Of course the larger is better. For the small ones everything is simple bur in large models there are many varieties.

1. One single sink - it's my favorite because you can wash even the biggest trays and pots with no problems.
2. Two different size basins - you can wash different items in the same time like food in one and plates in other or soap in the first one and rinse in the second. It is very comfortable but it would be a challenge to clean big pans in smaller one.
3.Two basins in equal size - I can decide if this is a good choice or not - on one hand you have to sinks but in other they are two small sinks which can be a problem in some cases. For me this is more design oriented than functional.
4. Triple sink - that's suitable for enormous kitchens but is very practical - you have two big enough basins and one small with rubbish disposal which is a big advantage.

When you know what size you want is time to choose the material you want to be made of.

 
1. Stainless steal - this material is literally non-destructible and your domestic cleaners will be very pleased if you choose this one because is very easy to clean.
2. Porcelain - it looks great and very stylish, can be cleaned easy with soap or gently rubbed with abrasive detergent for stubborn stains but it can be easily broken if you hit it with hard or heavy object.
3. Granite composite - it is scratches resistant and don't hold water but lighter composites can retain stains and need special maintenance.
4. Stone - it would look great especially if match with the counter top but you have to know that the natural soapstone can be easily scratched and chopped so you have to be very careful with it and to use special cleaning products to sanitize it.
These are the main things you have to know when you are searching for new kitchen sink. Of course there are so many details to think about such as the form of the sink - rectangle, oval, with rounded edges or what accessories to add to be more functional and comfortable such as rinse basket or sliding top to hide it while is not in use.