Why it matters
Single-letter domains are among the rarest assets in the market. They are short enough to be unique, but they are not always easy to brand because one letter has no meaning. Many .com versions are held by large companies and are not for sale. In other extensions, availability and prices vary by registry. A common mistake is paying a high price for a letter name with no clear plan. Buyers should ask what the name will do for the brand, and whether the owner will sell at all.
Source: en.wikipedia.org
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