Quoting LoadRunner documentation: VuGen enables you to add checks to your Web Vuser scripts. A check verifies the presence of a specific object on a Web page. The object can be a text string or an image. Web checks enable you to determine whether or not your Web site is functioning correctly while it is being accessed by many Vusers—that is, does the server return the correct Web pages? This is particularly important while your site is under the load of many users, a period when the server is more likely to return incorrect pages. You can read more in F1 help here: - VuGen > Protocols > Web Protocols > Text and Image Verification - VuGen > Protocols > Web Protocols > How to Add Text and Image Checks
