Your uniqname and UMICH password give you access to the University of Michigan's computing services. Every time you connect, you must provide the magic word; you must prove you're who you say you are. Should someone else guess or steal your password, he or she can masquerade as you, which means the intruder would then have access to your files, your e-mail, your funds, your personal information, and more. This intruder will have the power to modify or destroy your files, to send electronic mail threats in your name, or to subscribe to unwanted services for which you'd have to pay. In short, an insecure password can easily wreak havoc in your life.
And you won't be the only person affected by a stolen password. Other users on networks along the Internet could potentially be affected as well. Once an intruder with the necessary knowledge, experience, and tools gains entry to a system, he or she may be able to monitor other machines and systems on the same network and capture information about local users logging on to those machines. And if these users then connect to other networks, the intruder has the potential to penetrate and monitor the remote systems to which the local users connect, thereby increasing the likelihood of a breach in the security of those systems as well.