Microsoft Knowledge Base Article 319939 contains the following summary:
If you are using Windows XP, you can use the Point and Print functionality to print to shared printers that are hosted on computers that are running Microsoft Windows NT 4.0, Microsoft Windows 2000, Windows XP, and Windows Server 2003. If you use the Point and Print functionality to connect to a shared printer, the print driver for that shared printer is automatically downloaded to your workstation. This article describes how to use the Point and Print Restrictions policy setting.
Note It is possible for malicious users to embed viruses or other malicious code into a print driver. If you receive a damaged driver from a shared printer, your computer may be compromised.