As part of its new campaign, “Discovering Your Next Chapter: Lifelong Learning,’’ the Westborough Public Library is hosting a discussion on online data collection at 7 p.m. Wednesday. The free talk, entitled “Who’s Tracking You Online? The Quiet Big Data Revolution,” will be led by Greg Page, CEO and founder of Merrimack Analysis Group. During the interactive presentation, Page will discuss the positive, negative, and uncertain implications of online data collection, and ways that individuals can minimize their online footprint. For more information, call the library at 508-366-3050.