Cross-browser compatibility testing is a necessity in the face of modern web app development. At first, it would seem very baffling, but it really isn’t! You might have encountered an outage where your end users were not able to operate your product using a particular web browser. Flex, JavaScript, Applets, AJAX requests, Flash, and many more client-side components may behave differently on different web browsers. This happens due to rendering engines. The rendering engine is a part of a web browser which is responsible for presenting the content on various screens. This content could be text, images, or any other graphical representation. Every browser manufactured, be it Chrome, Mozilla Firefox, Safari, etc. has its own uniquely designed rendering engine. The process of checking that your web app stays compatible on various browsers is what we call cross-browser compatibility.
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