Q&A: how to tune a guitar?

Query by annaaa: how to tune a guitar?
I just received a guitar yesterday(i have no encounter with a guitar) and its out of tune.
So I experimented with going to youtube and i kinda got the sound but it appears so low and just not correct. any concepts why?

Best answer:

Answer by Erica!
http://www.gieson.com/Library/jobs/utilities/tuner/

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