If your Aunt Nellie is fond of sayings like "All's well that ends well," and "A penny saved is a penny earned," then she's a proverb expert. A proverb is a short, catchy phrase that expresses a true or useful idea.
Most proverbs have been around long enough, and endlessly repeated, that they are commonly seen as telling an important truth. People tend to use proverbs to give advice, the way you might say "practice makes perfect" to encourage your little brother to keep trying when he's learning to ride a bike. The Latin root proverbium combines the prefix pro with verbium, which together mean a word that you put forward, or a common saying.