You might see the difference in the name of both things.
A hairdryer, as you know, is a tool that helps to dry hair. This electronic equipment will result in hot air. Moreover, it is beneficial to style your hair into different themes.
A blow dryer is a tool that can dry any part of your body. However, it is also suitable to dry your hair. Mainly, it will result in cold air. At the same time, it has a ceramic heater that will give you hot air. Therefore, people with natural hair love this item to dry out their hair and get more volume.