Domain Names have a variety of basic rules, in general domains must:
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[*]Use only letters, numbers, or hyphen ("-").
[*]Not begin or end with a hyphen. - .com, .net, .org and .info domain names cannot exceed 67 characters total.
[*].info and .biz must have at least 3 characters not including .info or .biz.
[*]Other domain names cannot exceed 22 characters, not including the extension.
[*]Domain names are not case sensitive.
[*]Domain names cannot include spaces.
[*]2 letter domains are not permitted. Strictly speaking domain shouldn't begin with a number either, however, in practice, it is possible in most circumstances.
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