Today, most of us know that algorithms control what we see on Facebook or what we're recommended on Netflix.

And algorithms don't just pick news stories or TV shows for us.

They also influence our lives in the physical world.

But what exactly is an algorithm?

An algorithm, the way we teach it in college, is a sequence of well-defined steps that is designed

to get you from a set of inputs to a desired outcome.

This is Suresh Vanktusupramanian, a computer scientist at the University of Utah.

So what aspects of our lives do we perhaps not realize a control by algorithms, but actually they are?

At this point it would be easier for me to say all of them. I'd be less wrong by saying all of them than I would be by saying none of them.

These algorithms influence our lives in very subtle ways. For example, every time you call a lift...

Or an elevator, Tom.

Or an elevator. There's an algorithm that controls how it moves and therefore how long you have to wait.

But there are lots of different ways that algorithm could work.

Now the simplest thing you could do is keep track of who press the button first, go to that

person, take them where they need to go, then see who prick the button next,

and take them where they need to go. That would be sort of inefficient.

Fortunately, real elevators don't work this way. Instead, they have a slightly cleverer algorithm.

So another algorithm you could say is, let's not even worry about who press first.

Let me go up to the top or to the highest point where someone has made

a request and just pick up everyone I want to pick up along the way, deliver them to where

they need to go, and then when I come down to the same thing.

And that gets you very close to what elevator algorithms do right now.

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