What is pollination and why is it necessary for fruit production?

Pollination is when pollen is spread from one flower to another via different agents such as wind, insects, or birds. Our fruit trees, for example, are primarily pollinated by insects like bees! Pollination is how many plants, including our fruit trees, reproduce. When a flower is successfully pollinated, it will produce a fruit containing its fertile seeds, with the goal of someone then taking that fruit and helping to plant these seeds elsewhere. 

Pollination is key since if a fruit tree is not pollinated, it will not produce fruit.

Pollinizer vs Pollinator: technically, insects are pollinators, and trees themselves are pollinizers to each other (a source of pollen). However colloquially, we (most nurseries and general public) use pollinator in place of pollinizer, though it is incorrect. As it is so common a mistake that we all know what we mean, we will let it slide and stick with the masses in this case, as there are more important problems to solve and updates to make!