The ability to request information on-demand, such as data from another program or computer. The opposite of pull is push, where data is sent without request. The terms "push" and "pull" are used frequently to describe data sent over the Internet. The World Wide Web is based on pull technologies in that a page isn't delivered until a browser requests it.
Online examples of pull technologies include PQAs built for wireless devices, Blackberry (a browser-enabled wireless service), data-ready cell phones and palmtops, and even optimizing content for SEO (so it's easy for users to find information).