Do you know what the top 10 firms in the world by market capitalisation were at the end of 2010? No? I’ll tell you.

Exxon, Petro China, Apple, BHP Billiton, Microsoft, Industrial and Commercial Bank China, PetroBras, China Construction Bank, Royal Dutch Shell, and Nestle. The keywords? Banks, China, oil, computers and food. It’s a perfect snapshot of the world in the 21st Century. But the keyword that might not be so obvious is – the web.

For banks the web has been about connecting transactions and customers. For China the web has been about connecting its vast population, while at the same time preserving its sense of culture and government in the face of what it has seen as an assault from the Western world. Microsoft and Apple are two perfect examples of how the computer industry has had to react to the web.

Because it may seem axiomatic for the computer industry and the web to be inextricably tied but many computer businesses, in hardware and software, have failed because of the web.

Microsoft’s business was based on selling licenses of its most popular software to consumers and businesses. The web and its focus on access to information was a huge challenge for the company – it has forced a complete re-think of core products such as Windows and Office, as well as helping drive the future of Server products.

For Apple, the web has been the glue that has helped shift the company from purely a computer hardware firm, to a consumer electronics and services company.

And for Nestle? The web has been the tool that has allowed it to share its core messages, its brand values, to talk to customers and consumers. In essence, Nestle’s relationship with the web is a mirror of every company’s relationship with the web. The web connected us as consumers, it gave us access to information, and meant we could hear directly from firms about their products and services.

It wasn’t just about an e-commerce strategy. That’s just one small piece of the puzzle. The top 10 companies in the world today are the one’s who have realised that the web is the glue – between customers and between businesses.

And what of the future of business and the web? Well, three years ago Chris Anderson at Wired was predicting how free was the future of business. The web has ushered in radical new business models that 20 years ago would have been impossible, not to mention implausible.

The growth in wireless networks and the power of Moore’s Law means mobiles will become increasingly important and businesses that don’t account for this change will have no business at all. If your content and services are not easily accessible and practically usable on a mobile device then you are invisible to your customers.

If you’re not thinking how the web connects a phone to a supercomputer then you’re not thinking how a mobile phone is, in effect, the most powerful device ever made. Shouldn’t you want people who are carrying the most powerful computers in the world in their pockets as your customers?