Natural language processing (NLP) has many uses: sentiment analysis, topic detection, language detection, key phrase extraction, and document categorization.

Specifically, you can use NLP to:

• Classify documents. For instance, you can label documents as sensitive or spam.
• Do subsequent processing or searches. You can use NLP output for these purposes.
• Summarize text by identifying the entities that are present in the document.
• Tag documents with keywords. For the keywords, NLP can use identified entities.
• Do content-based search and retrieval. Tagging makes this functionality possible.
• Summarize a document's important topics. NLP can combine identified entities into topics.
• Categorize documents for navigation. For this purpose, NLP uses detected topics.
• Enumerate related documents based on a selected topic. For this purpose, NLP uses detected topics.
• Score text for sentiment. By using this functionality, you can assess the positive or negative tone of a document.

https://learn.microsoft.com/en-us/azure/architecture/data-guide/technology-choices/natural-language-processing