Explanation:

Common cold differs from pneumonia in that Pneumonia can be prevented by a live attenuated bacterial vaccine whereas the common cold has no effective vaccine.
Pneumonia is spread through bacteria or viruses that become present through something like coughing. If you are in close proximity with an infected person, you only need to breathe in the airborne virus to become infected. However, different types of pneumonia have different levels of infectious rates. Some, like mycoplasma pneumonia, are highly contagious, while others – such as pneumococcal pneumonia – are far less contagious and need ideal conditions to be transferred.
A cold is much more contagious than pneumonia. It is spread in the same way, through airborne droplets coming from coughing or sneezing, but the viruses are more easily picked up by anyone in proximity to the infected individual. That’s why it’s not uncommon to see an entire family sick after their infant begins showing cold symptoms.
A common cold can also be picked up by touching surfaces that have been infected. To get sick, an uninfected individual would have to touch the surface and then touch their mouth or lips, but it is still very possible to happen and it does happen often enough to be significant.