For the same reason people in the past would've had to know how to live off the ground, build shelter without any modern tools, make due with stone tools for everyday activities. Because in the world today basic computer skills are essential for living.
Many reasons man, cause the world is moving very fast, everything these days are about computers.
I want to place an order / make a reservation at a restaurant = computer !!
However, in some way, if this is a class assignment, the poster has already found one reason to be computer literate: research. There is no easier way in this day and age to reach out to the masses; particularly those masses computer literate enough to be online in the first place.