Aside from being one of the most fun words to say in science, the process of phagocytosis is pretty cool in itself. Remember the old video game Pac-Man? You guide the round, yellow character through a maze, dodging ghosts and gobbling up little dots. When Pac-Man opens his mouth and consumes one of the dots, it's a little bit like phagocytosis.
Endocytosis is a process through which a cell absorbs a particle, molecule, bacterium, or other type of matter by engulfing it. Phagocytosis refers to the engulfing of larger, solid particles. Often, the engulfed particle is another cell, like when a white blood cell, which is a part of the immune system, engulfs a bacterium to destroy it.
The basis of Principle of Immunization
By providing vaccination, we can .fool the immune system into developing a memory for a particular infection by putting something, that mimics the microbe we want to vaccinate against, into the body. This does not actually cause the disease but this would prevent any subsequent exposure to the infecting microbe from turning into actual disease