What is difference between a discrete variable and a continuous variable?

a continous variable is one that can assume different values at each point, so if you were measuring height it could be 187.1, 187.2.. 187.8, but this can not be used for something such as measuring the amount of people in a family, because there can't be 3.4 people in a family. This is when discrete variable is used, this measures full numbers.