14.1 Text Processing

Text processing is the first step in almost every NLP system. Raw text from websites, messages, or documents is messy: it has mixed cases, punctuation, extra spaces, and symbols. Before a model can learn from it, we clean and standardize it through steps such as lowercasing, removing punctuation, stripping stop words, and normalizing forms of the same word.

Imagine an Ethiopian bank wanting to analyze customer feedback messages in Amharic and English. Before counting complaints, it must remove emojis, fix spacing, and unify words like 'Bank', 'bank', and 'BANK' into one form — otherwise the same word would be counted as three different things.