Asked about What a token is

Why use subword tokens rather than words or characters?

An answer that works

Characters make sequences too long, and sequence length drives cost and compute. Whole words need an impossibly large vocabulary and cannot handle unseen words. Subwords give a fixed vocabulary that can still represent anything.

Reading an answer is not being able to give one. The section that teaches this is What a token is, 2 hours of Tokenization.

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