Regression algorithms are used to determine continuous values such as price, income, age, etc.

Classification algorithms are used to forecast or classify the distinct values such as Real or False, Male or Female, Spam or Not Spam, etc.

Fundamentally, classification is about predicting a discrete label. Eg: Pass/Fail, Promoted/Not Promoted

Regression is about predicting a continuous quantity. Eg: Date of Payment, Height/Weight etc.