 Requiring workers to memorize their passwords rather than writing them down in a place that might be observed by an onlooker (maybe a colleague, visitor or intruder) is an example of risk avoidance.Computers plainly need electrical power, hence they are vulnerable to issues such as power cuts, accidental disconnection, flat batteries, brown-outs, surges, spikes, electrical interference and electronic failures.Physical information security controls to address the associated risks include