Tome names must be between 4 and 100 characters long, and may contain only upper or lowercase letters, numbers, or dashes.
The name you choose will form the address for the tome, for example a tome named "userguide", has the address:
Because the tome name is used in URLs, you should ensure that it is something that is broadly descriptive or relevant to the content.
You can change a tome name later, as long as the new name you want is not already taken. However, it is strongly advised NOT to do this once a tome is established, as existing links in search engines, forums and so on to your tome will no longer work. It makes sense to think carefully about your tome name and get it right first time.