Information extraction from external sites

[gavinmcnamee]

I have been a bit miffed as to how websites can go and search other website and bring back information to compare?

The site i am talking about are site that compare prices for various thing like flights, electrical goods, financial products etc...

How do you extract this info? Do you need to contact the sites webmaster and as for access to there product database? Can you just do it regardless? Can it be done with basic php?

Can any one please enlighten me?

Any snippets of advice of info would be very helpful

Thanx

gavin

[PHP_Chimp]

have a look at the curl [uk.php.net] functions.
As they can be used to find information if you know where you are looking.

[gavinmcnamee]

I don't realy quite understand cURL. Are there any good tutorials or alternatives regarding a price comparison website?

[PHP_Chimp]

Google is your friend. There are plenty or tutorial out there to help you get started with curl.