We've all heard it and as guitarists we try everything we can think of to avoid it. Usually it's an easy fix and hopefully after reading this it will plague you no longer. Fret buzz is as the name suggests a buzzing sound created when playing guitar and is usually caused by one of two things. Technique or guitar maintenance (sometimes both), below I will outline how to eliminate fret buzz and make your guitar sing as smooth as butter.
How to check technique
Firstly just start playing until you hear the fret buzz, once you've managed to create that terrible sound there are a few things you can do with your fingers and positioning to eliminate it.
The simplest is to press down harder, 9 times out of 10 is is due to not pressing down hard enough on the strings, try playing some chords or a lead line and if you get buzz, play it again but this time pressing down much harder until the buzz is eliminated.
If that fixes it then great, you just need to work on finger strength and play as much as you can until you develop more strength. If that does't solve it then it might be finger positioning, is your finger in the middle of the two frets? Or close to it? Make sure your finger isn't too close to the actually fret as this will also cause fret buzz.
If technique is good...
Then this probably means it's your guitar, if so then the simplest fix is a new set of guitar strings, after time the strings will get coated with oils from your fingers and all kinds of other stuff which can create fret buzz. After a good clean and new set of strings there should be no fret buzz providing your technique is good too.
If all else fails then it might be a bigger issue with your guitar, such as frets being incorrectly positioned, issues with the 'nut' of the guitar, or electrical issues, I would advise that you take your guitar to a music shop and they will assess this for you.
That's it for today thanks for reading!