A messenger bag is a neat bag that you carry over your shoulder and easy to take to school or work. There are different types, sizes and colors of messenger bags, but they all have a laptop compartment. For example, there are messenger bags for women and messenger bags for men. Which bag suits you best depends not only on the color and material, but also on the size of the laptop compartment. When making your choice, make sure that your laptop fits in the messenger bag.