RGB is the same as component. This pisses me off so bad. To elaborate, RGB does fit the broader definition of component video- video broken up into separate components. However, when people say component, they usually mean color difference, or YPbPr. They are definitely not the same. YPbPr separates the video into Y, or luma (brightness), Pb (difference between blue and luma) and Pr (difference between red and luma). Why anyone would come up with such a ludicrously overcomplicated method I will never understand, especially since it came into use in the digital age. RGB, on the other hand, simply has lines for Red, Green, and Blue. Of course, there are differences in the sync rate and how it's transmitted. With YPbPr sync is on the Y line. With RGB it's on a separate sync line. The two are totally incompatible and barely related. Why do people get mixed up? Well, the component jacks are colored red, green and blue, even though green is actually luma. So, some people think they are the same, some use the terms pretty much interchangably, and worst of all, some people actually call component RGB. My explaination is probably crap, there's a much better one on GameSX.
RGB=VGA. Again, no. Why do people think these are the same? Because they are very similar. Both have separated Red, Green, and Blue lines for video. The difference lies in the sync rate and by extension resolution. VGA has a 31KHz horizontal sync rate. RGB has a 15KHz horizontal sync rate. Additionally, VGA uses separate Hsync and Vsync lines, whereas RGB only has a composite sync line. Now technically, VGA is also a form of RGB, but in the portabilizing and retro gaming world, RGB typically refers to the 15KHz RGB I just talked about. Again, GameSX has a better explaination.