--- title: Learn Computing from the Experts | The Rheinwerk Computing Blog | Bert Gollnick description: Bert Gollnick is a senior data scientist who specializes in renewable energies. For many years, he has taught courses about data science and machine learning, and more recently, about generative AI and natural language processing. Bert studied aeronautics at the Technical University of Berlin and economics at the University of Hagen. His main areas of interest are machine learning and data science. --- [![Rheinwerk Computing Logo](https://blog.rheinwerk-computing.com/hubfs/computing_logo-header.svg)](https://blog.rheinwerk-computing.com/) [Blog](https://blog.rheinwerk-computing.com) - Books - Get an overview of our wide selection of books on every relevant computing topic. - [General Computing](https://www.sap-press.com/rheinwerk-computing/general-computing/) - [DevOps](https://www.sap-press.com/rheinwerk-computing/devops/) - [Programming Languages](https://www.sap-press.com/rheinwerk-computing/programming-languages/) - [Security](https://www.sap-press.com/rheinwerk-computing/security/) - [Software Development](https://www.sap-press.com/rheinwerk-computing/software-development/) - Book Subscription - Get unlimited access to all Rheinwerk Computing books! - [Programming Subscription](https://sap-press.com/subscriptions/) ![](https://blog.rheinwerk-computing.com/hs-fs/hubfs/How%20to%20Write%20Your%20Own%20Python%20Functions.jpg?width=1000&name=How%20to%20Write%20Your%20Own%20Python%20Functions.jpg) [Featured](https://blog.rheinwerk-computing.com/tag/featured) | Featured article ## [How to Write Your Own Python Functions](https://blog.rheinwerk-computing.com/how-to-write-your-own-python-functions) Functions in Python provide functionality that you or someone else has already pro­grammed. In this post, we’ll teach you how to write your own Python functions. ![Rheinwerk Computing](https://blog.rheinwerk-computing.com/hubfs/RW-logo-300x300.png) by [Rheinwerk Computing](https://blog.rheinwerk-computing.com/author/rheinwerk-computing) [Read More](https://blog.rheinwerk-computing.com/how-to-write-your-own-python-functions) ![Bert Gollnick](https://blog.rheinwerk-computing.com/hubfs/Bert%20Gollnick.jpg) **Bert Gollnick** Bert Gollnick is a senior data scientist who specializes in renewable energies. For many years, he has taught courses about data science and machine learning, and more recently, about generative AI and natural language processing. Bert studied aeronautics at the Technical University of Berlin and economics at the University of Hagen. His main areas of interest are machine learning and data science. # Blogs by Bert Gollnick [![How to Chat with Your Data: The Power of Retrieval-Augmented Generation (RAG)](https://blog.rheinwerk-computing.com/hs-fs/hubfs/How%20to%20Chat%20with%20Your%20Data_%20The%20Power%20of%20Retrieval-Augmented%20Generation%20(RAG).jpg?height=600&name=How%20to%20Chat%20with%20Your%20Data_%20The%20Power%20of%20Retrieval-Augmented%20Generation%20(RAG).jpg)](https://blog.rheinwerk-computing.com/how-to-chat-with-your-data-the-power-of-retrieval-augmented-generation-rag) [Artificial Intelligence](https://blog.rheinwerk-computing.com/tag/artificial-intelligence) ## [How to Chat with Your Data: The Power of Retrieval-Augmented Generation (RAG)](https://blog.rheinwerk-computing.com/how-to-chat-with-your-data-the-power-of-retrieval-augmented-generation-rag) Large language models (LLMs) are often described as massive and all-knowing, and in many ways, they are. They have spectacular abilities. They can... ![Bert Gollnick](https://blog.rheinwerk-computing.com/hubfs/Bert%20Gollnick.jpg) by [Bert Gollnick](https://blog.rheinwerk-computing.com/author/bert-gollnick) [Read More](https://blog.rheinwerk-computing.com/how-to-chat-with-your-data-the-power-of-retrieval-augmented-generation-rag) ### Blog Topics - [All Topics](https://blog.rheinwerk-computing.com) - [Programming Languages](https://blog.rheinwerk-computing.com/tag/programming-languages) - [How To](https://blog.rheinwerk-computing.com/tag/how-to) - [JavaScript](https://blog.rheinwerk-computing.com/tag/javascript) - [DevOps](https://blog.rheinwerk-computing.com/tag/devops) - [Featured](https://blog.rheinwerk-computing.com/tag/featured) - [Web Development](https://blog.rheinwerk-computing.com/tag/web-development) - [What Is?](https://blog.rheinwerk-computing.com/tag/what-is) - [Cybersecurity](https://blog.rheinwerk-computing.com/tag/cybersecurity) - [Artificial Intelligence](https://blog.rheinwerk-computing.com/tag/artificial-intelligence) - [Software Development](https://blog.rheinwerk-computing.com/tag/software-development) **Subscribe to our blog!**Get notified about future blog updates. - - - ### Most Popular Blog Posts 1. 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