If your computer is going to be off for more than a few minutes, it is recommended that you shut it down completely. It is important to remember that you should completely shut down your computer at least once a day. Extended periods of use can lead to system instability, and a restart gives your computer a chance to refresh.
Stand By is a feature that you can use on your laptop that will put your computer into a power-saving mode without turning it off. This is convenient if you are moving between classes or locations in the library, but should never be used if your computer is going to be off for more than a few minutes. Extended use of the stand by feature can cause several problems with your PC including slow response time, lose of the wireless or network resources, freezing, or even loss of data.
The Hibernate function is also an alternative to stand by for longer periods of inactivity. This saves everything in memory to your laptop's hard drive and completely powers down the computer. In turn, the startup time is faster than it would be when starting up from a complete shutdown. This too, unfortunately, has its drawbacks, which can be the same as those experienced with stand by mode.