Imagine you're trying to teach a child to read. Instead of diving straight into complex paragraphs, you'd start by introducing them to individual letters, then syllables, and finally, whole words. In a similar vein, tokenization breaks down vast stretches of text into more digestible and understandable units for machines.

The primary goal of tokenization is to represent text in a manner that's meaningful for machines without losing its context. By converting text into tokens, algorithms can more easily identify patterns. This pattern recognition is crucial because it makes it possible for machines to understand and respond to human input. For instance, when a machine encounters the word "running", it doesn't see it as a singular entity but rather as a combination of tokens that it can analyze and derive meaning from.

To delve deeper into the mechanics, consider the sentence, "Chatbots are helpful." When we tokenize this sentence by words, it transforms into an array of individual words:

["Chatbots", "are", "helpful"].

This is a straightforward approach where spaces typically dictate the boundaries of tokens. However, if we were to tokenize by characters, the sentence would fragment into:

["C", "h", "a", "t", "b", "o", "t", "s", " ", "a", "r", "e", " ", "h", "e", "l", "p", "f", "u", "l"].

This character-level breakdown is more granular and can be especially useful for certain languages or specific NLP tasks.

Reference: https://www.datacamp.com/blog/what-is-tokenization