After I got this to work I copied the code in order to make a clear button / function. I've been having problems, even though the code seems to be identical. This is likely an obvious question, pardon my inexperience.
Beer Counter
var beers = 0
var output =""
function beer()
{
beers = beers + 1
output = document.getElementById('output')
output.value = beers
}
function clear()
{
beers = 0
output = document.getElementById('output')
output.value = beers
}
Beer count: