And hope that the base and the cord and the circuit are all wired correctly so that, even with the switch off, you don't have a hot lead going to the base of the bulb. Especially the case when the switch is part of the light fixture, like a table lamp (of course, then just unplug the thing -- but people often don't because the outlet is behind some heavy piece of furniture or something).I remove broken light bulbs by jamming the tip of some needle-nose pliers up into the base, then pulling the handles apart so that the tips spread and grab the inside of the base. Then it unscrews quite well. BUT ALWAYS WEAR SAFETY GLASSES when doing this because there are often some glass fragments. AND switch off the power to avoid tripping the circuit breaker or popping a fuse.