People often confuse colds and the flu - and use the terms interchangeably.  But, there is a difference.

The common cold is caused by a variety of different viruses, all of which typically lead to coughing, sneezing, a runny nose, and a sore throat.

The flu is caused by the influenza virus, and can include many of the same symptoms of the common cold.  But, the flu can infect the lungs and intestinal tract.  One other important difference between the two is that while there isn't a vaccine for the common cold, there is one for influenza.

To learn more, follow the link below.

What's the difference between cold and flu?: Scientific American.