Sneezing or....

If you just sneezed, something was probably irritating or tickling the inside of your nose. Sneezing, also called sternutation, is your body's way of removing an irritation from your nose.
When the inside of your nose gets a tickle, a message is sent to a special part of your brain called the sneeze center. The sneeze center then sends a message to all the muscles that have to work together to create the amazingly complicated process that we call the sneeze.