Sweat equity is a term used to describe when you use your own hard work, instead of money, to increase the value of something. For example, if you buy a house to fix up and you work hard to paint it, fix the roof, and do other improvements, then the value of your house will be higher than it was before you started. You have increased the value of the house with your own hard work, sort of like using 'sweat' instead of money.