By Spencer Kelly Reporter, BBC Click Online

In the second of Click Online's series looking at competition among the big portals and search engines, Spencer Kelly reports on how the battleground is going global, in more senses than one.

The fascinating satellite images have a business driver behind them

A few weeks ago, the web world was captivated by the stunning images produced by Google Earth, an interactive 3D model of the globe.

The ground detail is a montage of satellite images, which means you can zoom in to very, very high detail.

In some cities this is complemented by 3D models of individual buildings.

And because it would be crazy not to, it can also be overlaid with road maps to give you directions from A to B. If you insist, it will even fly the route for you.

It is certainly a far cry from the online maps that we have been used to.

All the satellite images are stored on the web, not on your computer.

As you zoom in, more and more detailed images are loaded, assuming that your internet connection and PC are fast enough.

New market

But behind the sexy satellite images and cool technology, there is a serious business plan called "local search".

Many search engines and portals now have a Local section, and they have been quietly building up their databases of road maps, and directories of local businesses, for a while.

Enter a postal code, street or area, and a type of business, and you are presented with a list of your nearest options.

Not all cities and countries are mapped to the same level of detail

"Local listings is a billion dollar business," says Google's Lorraine Twohill.

"It's an extremely interesting business for everybody, the ability to allow small businesses to get on the web.

"Typically 90% of small businesses still don't have websites, even in this day and age, because they're a corner florist or a little pizza place - why would they need a website?

"This is a way for them to get access to the web and be part of that experience. So when users are looking for them they're finding the big guys but they're also finding the corner stores."

Popular vision

Google Earth has certainly hogged the limelight, but as we are discovering in this series, good ideas are rarely original.

One day before Google Earth emerged, MSN launched Virtual Earth. It is not 3D, but the idea is pretty much the same.

The always-on nature of broadband means it's now realistic to not reach for your bookshelf for the local telephone directory but actually just go online Nick Hazell, Yahoo

And just this week Amazon unveiled a slightly different take on mapping - street maps accompanied by millions of ground level photos in 22 major US cities.

Yahoo's Nick Hazell says: "Local search has become a really interesting area of innovation for us over the last few months."

"Thinking about the trends that have led to that, the first one is the widespread adoption of broadband.

"The always-on nature of broadband means that it's now realistic to not reach for your bookshelf for the local telephone directory but actually just go online and get a much richer experience around searching for that pizza restaurant, or whatever it happens to be.

"It could be user reviews, traffic directions and in fact whether there are any traffic queues between you and the pizza restaurant."

On the move

Yahoo is providing traffic information. MSN also has general traffic info. Google is even helping you find a cab, with Google Ride Finder, in conjunction with GPS-enabled taxis.

SEARCH ENGINES SERIES Part one: Search engine race gets personal Part two: Portal race goes local and global Part three: coming up next week...

It is easy to see how this technology will be extremely useful on the move, once the connection speeds of mobile devices are sufficient.

MSN's Stuart Anderson believes: "We're spoilt for choice with mapping software on the internet. There are lots of people that are doing great stuff.

"For me, services that are going to change the way we use mapping software, the way that we do use things like satellite images, is the way it integrates into other services, whether it be pushing to mobile phones, pushing to e-mail, pushing to friends in Messenger.

"It's how you use that that'll change the way you use the internet."

Room for improvement

Most of the latest local search and satellite imaging features are still in the early stages, and no-one is pretending they are perfect yet.

For example, the satellite pictures themselves will not necessarily be bang up to date and some buildings now occupied may appear still to be building sites.

But the biggest drawback is that only a few countries have been mapped in any detail at all.

It is no surprise that many American cities have very detailed satellite images, with local business listings and road maps, but many other countries are less well covered.

Practical problems aside, there is no denying the "wow" factor of interactive satellite mapping

Lorraine Twohill says it is not very difficult to add other countries.

"We have the content already, it's just a question of when we're ready as a business and when we can actually make it a practical application.

"We're obviously going to roll Local out to new markets. There's many components to Local; one major component is your partner in terms of listings. We're obviously talking to key partners in each country.

"There's a lot of work around bringing Local and maps as a combined entity to a marketplace."

When it comes to driving directions, we are still faced with the same practical problems - they are confusing automated instructions based on road names and numbers, not common sense.

Practical problems aside, there is no denying the "wow" factor of interactive satellite mapping.

And because Google is slightly barmy - and because it can - it is not just Earth maps that are available: why not try Google Moon.

Zoom in to the lunar landing sites, or just zoom in as far as you can go to see if the rumours are true...

Click Online is broadcast on BBC News 24: Saturday at 2030, Sunday at 0430 and 1630, and on Monday at 0030. A short version is also shown on BBC Two: Saturday at 0645 and BBC One: Sunday at 0730 . Also BBC World.