Mozilla Firefox vs Internet Explorer. Internet Explorer was launched by Microsoft in 1995 and Firefox was released by the Mozilla Corporation in 2004. One key difference between the two is that Internet Explorer can only be used with Windows, whereas Firefox is compatible with many other operating systems. Another advantage that Firefox has over Internet Explorer is that it is an open source, free web browser. This allows people to customize and create more features as there are plenty of add-ons that are available. An additional way that Firefox can be further customized is that it can be optimized to render pages faster. This is not an option with Internet Explorer. Firefox can provide you with a more tailor-made user experience.