It should also be noted that components can implement multiple interfaces. This is something we'll return to later when we discuss '''interface querying'''.

For this walkthrough we will use the Mozilla build system to create our component. It is also possible to us the '''Gecko SDK''' ([http://developer.mozilla.org/en/docs/How_to_build_a_binary_XPCOM_component_using_Visual_Studio instructions are here]). NOTE: this assumes that you have already done a successful objdir-Firefox build.