LLLL.com, VCVC.com etc

[quadnames]

I see all of these combinations referenced. WOuld anyone take a moment and tell me what they all mean? I know that LLLL.com is all apha-character 4ltr .com names (I think). Any help would be appreciated.

 

[theinvestor]

LLLL.com - Letter Letter Letter Letter
CCCC.com - Character Character Character Character
NNNN.com - Number Number Number Number
VVVV.com - Vowel Vowel Vowel Vowel
VCVC.com Vowel Consonant Vowel Consonant