LLM Tokenization
Tokenization is a fundamental process in preparing text for Large Language Models (LLMs). It converts input text into smaller units called tokens, which are the basic elements LLMs use for analysis and generation.
The Tokenization Process
- Preprocessing: Cleaning up the text
- Remove special characters
- Eliminate common words (stop words) like "the" or "and"
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Trim extra whitespace
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Initial Segmentation:
- Split text into sentences
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Break sentences into words
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Main Tokenization: Two primary approaches
- Word-level: Divide text into individual words
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Subword-level: Break words into smaller, meaningful parts
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Token Representation:
- Each token gets a unique ID
- IDs correspond to entries in the model's vocabulary
Example: Input: "The quick brown fox jumps over the lazy dog" Tokens: ["The", "quick", "brown", "fox", "jumps", "over", "the", "lazy", "dog"] Token IDs: [1, 2, 3, 4, 5, 6, 7, 8, 9]
- Vocabulary: The model's token dictionary
- Contains all unique tokens the model knows
- Created during model training
- Maps tokens to their IDs
Tokenization Strategies and Techniques
- Word Tokenization: Splits text into whole words
- Subword Tokenization: Breaks words into smaller units
- Byte Pair Encoding (BPE): Popular subword algorithm
- WordPiece: Alternative subword method
- Unigram: Approach based on single units of meaning
By converting text into tokens, LLMs can effectively process and understand language input, leading to more accurate analysis and generation of human-like text.