(Pocket-lint) - Online grocery shopping is not new in the slightest, but we recently realised that we still know very little about it.

We know how to place an order with the different supermarket chains that offer the service. And we know about the deliveries themselves, including the sometimes excessive and odd substitutions that appear at the door. But we have to admit that we didn't really realise how our items end up in bags or boxes after we've checked out.

To be honest, we always thought a spotty oik called Jeremy or something trudged around the supermarket, picking our items from the shelves - only occasionally checking to make sure the best before date was almost but not quite expired. And that still might be the case with some stores.

Ocado, however, has revealed its picking system and the reality is much more high tech than we expected.

It actually employs 1,100 robots to help with the picking, with a claimed accuracy of 98.9 per cent. And that's just in its Andover fulfilment centre. There are other warehouses around the UK.

The robots pick whizz around, picking up the necessary crates and delivering them back to "personal shoppers" that then assemble the orders. Jeremy still gets a job but doesn't have to tread the aisles himself. Which is just as well, as Ocado doesn't have any being online only.

The robots are custom built and programmed, having been designed by Ocado Engineering and Ocado Technology. And they are part of the "most efficient warehouse logistics solution" ever designed.

So when you next get your carrots, you know now how they were chosen for you.

Writing by Rik Henderson.