Domain names are composed of letters and numbers. Theoretically, all domain names are regular and can be traversed. However, the actual domain names in use are not consecutive and can usually be considered irregular. It’s like an array [2,3,5,7,11,13,17,19,23,29,31…], with many gaps in the middle. The domain name is also similar. A long and irregular domain name like abc123zzz.com cannot be judged whether it is valid. "Looseness" will affect the search engine's data capture. You cannot completely traverse all domain names in a regular way such as scanning a.com, b.com... and you can only find other methods.
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Domain names are composed of letters and numbers. Theoretically, all domain names are regular and can be traversed.
However, the actual domain names in use are not consecutive and can usually be considered irregular.
It’s like an array [2,3,5,7,11,13,17,19,23,29,31…], with many gaps in the middle.
The domain name is also similar. A long and irregular domain name like abc123zzz.com cannot be judged whether it is valid.
"Looseness" will affect the search engine's data capture. You cannot completely traverse all domain names in a regular way such as scanning a.com, b.com... and you can only find other methods.