A spill proof cup or more commonly known as a sippy cup is a cup made for children who are learning how to drink out of a cup. They are used between bottles and a regular cup. The cup is made from plastic and the top has a raised slanted spout so your kids can drink from it. Inside the cup it has plastic insert that controls the amount of liquid that your child can drink. The trouble with kids learning to drink from a standard cup is that they drink too fast and the drink comes out too fast More...