The sippy cup is a spill-proof drinking cup designed for toddler

Toddler

A toddler is a young child, usually defined as being between the ages of one and three. Registered nurse, midwife and author, Robin Barker, states 'Any time from eight months onwards your baby will begin to realise he is a separate person from you...

s. It works by way of surface tension

Surface tension

Surface tension is a property of the surface of a liquid that allows it to resist an external force. It is revealed, for example, in floating of some objects on the surface of water, even though they are denser than water, and in the ability of some insects to run on the water surface...

 that prevents liquid from being spilled even when the cup is upended. The critical element is the sippy top being firmly in place on top of the cup, preventing spills.

The sippy cup was invented by Richard Belanger, who licensed the design to Playtex

Playtex

Playtex and PlayTex are a brand and trademark. It used to be associated with bras and women's undergarments. Currently there are two separate companies with the Playtex name....

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