Reddit is introducing a new ad format that looks similar to posts made by users on the platform, the company announcedon Thursday. The launch comes as Reddit is readying its initial public offering (IPO). The new ad format, called free-form ads, is designed to feel similar to the content that users share with each other in order to help advertisers get maximum engagement. Although the new format may be enticing to advertisers, ads that look like regular posts may not be a welcome addition for users.