For example, amorphous names such as rivers, mythological places and other impossibilities are very suitable. Don't use antagonistic or otherwise embarrassing names. But if you ever give someone a demo on your machine, you may find that they are distracted by seeing a nasty word on your screen. Why bother taking the chance that they will be turned off by something completely irrelevant to your demo. Don't use digits at the beginning of the name.
Many programs accept a numerical internet address as well as a name.
Unfortunately, some programs do not correctly distinguish between the two and may be fooled, for example, by a string beginning with a decimal digit. Don't use non-alphanumeric characters in a name. Your own computer may handle punctuation or control characters in a name, but most others do not. If you ever expect to connect your computer to a heterogeneous network, you can count on a variety of interpretations of non-alphanumeric characters in names. Network conventions on this are surprisingly nonstandard.