Reference 3 stops to get here

BOS Token

Beginning Of Sequence token - marks the start of a sequence in language models.

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3 stops · basics first
  1. Token ✓ understood

    The unit of text a language model reads and writes: a word, part of a word, or a character, drawn from the model's fixed vocabulary.

  2. Tokenization ✓ understood

    Splitting text into tokens, usually subword pieces, and mapping each to an integer ID so a language model can process it.

  3. Special Token ✓ understood

    Reserved tokens with special meanings like [CLS], [SEP], [MASK], [PAD] used in various model architectures.

  4. BOS Token · you are here ✓ understood

Beginning Of Sequence token - marks the start of a sequence in language models.

This concept is essential for understanding large language models and forms a key part of modern AI systems.

  • Special Token
  • EOS Token
  • Tokenization

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Language & LLMs EOS Token End Of Sequence token - signals when the model has finished generating a complete output. Language & LLMs Padding Token A special token used to make sequences the same length in a batch, typically ignored during computation. Language & LLMs Tokenization Splitting text into tokens, usually subword pieces, and mapping each to an integer ID so a language model can process it.