A token is a sequence of characters that plays a certain role in a written language. In the context of natural language processing (NLP), tokens are the smallest text units processed by NLP algorithms. Tokens can be words, phrases, punctuation marks, or individual characters.
For example, the sentence “The quick brown fox jumps over the lazy dog” can be tokenized into the following sequence of tokens:
"The" "quick" "brown" "fox" "jumps" "over" "the" "lazy" "dog"
NLP algorithms use tokens to represent the meaning of text. For example, a machine translation algorithm might use tokens to translate a sentence from one language to another. Or, a sentiment analysis algorithm might use tokens to identify the sentiment of a text, such as whether it is positive, negative, or neutral.
Here are some examples of how tokens are used in different NLP tasks:
- Text classification: A text classification algorithm might use tokens to classify a text into a particular category, such as news, sports, or entertainment.
- Question answering: A question-answering algorithm might use tokens to extract the answer to a question from a text.
- Summarization: A summarization algorithm might use tokens to generate a text summary.
Tokens are the building blocks of NLP and essential for many NLP tasks. Product researchers can develop more effective and accurate NLP solutions by understanding what tokens are and how they are used.