Your frets might be crooked, try bringing it to an instrument repair man, he'll know how to fix it.
It depends on where you have it. Try restringing your guitar, see it that fixes it. And what kind of climate do you keep your guitar? If its wet a lot, the neck could be absorbing water.
If it's an electric guitar, it might be your amp, or your pickups. If its acoustic take out the strings, and try replacing them. However, if you're not satisfied with that mediocre (at best) response, try this. The strings on a guitary don't buzz, uneven frets do. If a fret is buzzing and it continues even after you replace old strings, (the dead skin on which acts as a medium to create a false uneveness to the fret) then the buzzing must be fixed by either having a new fret put in, or having the action adjusted by the truss rod. A guitar string will never buzz, it's the fret itself that causes the buzzing.
USUALLY what happens is that chords buzz when they are in sync together like when you ture the guitar when they are in tune they buzz
Might be because the action on the strings is too low, basically, your strings are too close to your fretboard. everytime you pluck one it will vibrate against the frets, try to set them up a bit higher. or turn them a bit tighter, this might do the trick.
how well it stays in tune if its comfortable, no say splinters on the neck no fret buzz (notes buzz when their not supposed to) low action (low to the neck strings) lots of sustain (the notes don't die quick) good sounding pickups that's guidelines I suppose.
go to a store and ask them
I would suggest Ernie Ball: Hybrid Slinkies. They are an extra light gauge so the child's fingers can easily push them down against the neck. They also have less tendency to buzz on the frets if not held down entirely. Also, if you are teaching a child how to play Electric Guitar, you may want to try a guitar that is a 1/4 scale with a thin neck. Ibanez has a GRGM21 Mikro that is great for kids.
Bad: strings buzz, bent neck, bad strings, etc. general bad guitar things
Try to fix the nut. the strings could have moved it a little. i had the same problem when i restrung my guitar.
When he realised Buzz LightYear got to the moon first
the idea of the name buzz lightyear came from the second man on the moon's first name, buzz aldrin. oh, and his names actually buzz lightyear not buzz lightning.
Neil Armstrong and Buzz Aldrin. Neil was first, Buzz was second.