What is the best age for a child to start school

If you look at twenty years back, we use to start school at the ages of five years and above and we were able to make it. But these days’ people send their children to school at the age of one, two and some even halve a year.

How I do ask myself is that: what will a child who is not up to a year or cannot talk benefit from going to school?

Are we not wasting our money, energy and time? So what do you think should be the right age to start school?