How do I invoke web services? I am working on a site, and I want to integrate my site with an external site; for that, I need to use web services to get data from the external server. I don't know the technology used by the server.

I have to work as client. Can any one please tell me hoe to call web services from my site? Please write any code if it is required. Will drupal_http_request() help me?

I am using Drupal 6.
You should have a look at the Services module. You can use XMLRPC and/or REST server (and many more) to communicate with your remote server. Link to the documentation.


  A standardized solution of integrating external applications with Drupal. Service callbacks may be used with multiple interfaces like REST, XMLRPC, JSON, JSON-RPC, SOAP, AMF, etc. This allows a Drupal site to provide web services via multiple interfaces while using the same callback code.