I counted and we have 20 different types of light bulbs in this house. Twenty. Many of them are funky in the ceiling types that are hard to change and quite expensive. So I hit amazon.co.uk and bought a bunch on line. They were much cheaper. But, you know, you get what you pay for. They don't seem to be lasting two months at the moment. So I'm constantly up the ladder changing light bulbs. We have all sorts in this house. I have learned the difference between normal screw type, bayonet, SES, GU-10, the type with two wires sticking out, amongst others. The worst are these GU-10 halogens that are all over the house, they are a bitch to insert into the in-ceiling fittings and seem to burn out all the time. I thought of going with LED replacements but these are around five punds each (at the cheapest), whereas I got 12 of the halogens for a fiver on amazon. Why so many kinds of bulbs I want to know?