The only thing that damages beer is direct sunlight: beer is best kept in the dark. In fact, the bottles breweries use are either amber or green in colour, making it harder for light to filter through.
Drinking draught beer is a fundamental part of beer tasting. First of all, you should never ask for beer without a head: bottom fermented beers should have an inch and a half of head on them. Instead, some top fermented beers may not need a head.

Why is a beer head necessary? First of all, without its natural “lid”, beer loses its aroma and fragrance quicker and this would be a real shame with a live product like beer. Secondly, the beer would experience a sudden increase in temperature that stops it from being at its best.

Every beer must be poured into the right kind of glass, which should be perfectly clean and well rinsed. Any amount of detergent can immediately be traced, as it reduces the amount of head. For a perfectly drawn draught beer, glasses should be dipped in water first. This lowers the temperature of the glass, and thus avoids a temperature shock when beer is poured into a warm glass and also ensures that the beer head does not stick to the sides of the glass and therefore stays intact for longer.