Google is trying to be like a big net that gets cast out and brings back the best possible answers for the solution. So if you want to rank for online guitar lessons but don’t have something on the page for acoustic guitar lessons, online electric guitar lessons, etc what does that tell Google? That you’re page is very narrow and it only applies to one search. So you want to have one page that is about an entire topic. If a person types in online guitar lessons they could be looking for acoustic guitar lessons or electric guitar lessons and Google knows this and that’s why when someone does a search Google brings up a page that has the best chance of answering everything.
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