Most people barely know how any technology they use, including something as simple as a light bulb, actually works. Most technology might as well be magic as far as most people are concerned. The blame, at least partially, properly belongs with companies that produce insecure operating systems, websites (no reason that passwords should ever be sent over the network in clear text, for example) designers/operators, networks, and so on. For example, why isn't wireless networking traffic encrypted by default? Truth be told, the PC is not really ready for general home use for sensitive applications, as it really needs an expert to secure it (and even then, you're still susceptible to software with memory leaks, unbounded arrays, and so on).
Very simple. Flip the switch to the "on" position.