Kassey Lee: Why are Pinyin domains also known as 1-pin, 2-pin, 3-pin, and 4-pin

[Digital Pandit]

Kassey Lee explains the nomenclature for Pinyin domain names.

When talking about Pinyin domains, I often use the terms 1-pin, 2-pin, 3-pin, and 4-pin. Where did they come from and why are they important?

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