It is possible to determine someone's interests and hobbies through their borrowing history from a library, but this involves some important privacy and ethical issues. Under the premise of protecting user privacy, the following analyses can be performed: 1. **Book category analysis**: Looking at the categories of books someone has borrowed (such as literature, science fiction, history, etc.) can provide a preliminary judgment of their interests. 2. **Theme or keyword analysis**: Based on the themes or keywords of the books, you can get a more detailed understanding of someone's interests in specific areas, such as their interest in a certain historical period or a specific person. 3. **Frequency and quantity**: The frequency and quantity of borrowing can also reflect the degree of interest. For example, if someone frequently borrows books about photography, it may indicate that they have a strong interest in photography. 4. **Change trend**: If a person's interest in a certain topic increases over time, it may indicate that their interest in the topic has increased. However, this analysis must comply with relevant privacy regulations and policies. Libraries generally protect the privacy of borrowers, so the use of this data requires strict regulations and usually requires the consent of the borrower. In addition, the results of the analysis are only a guess and are not necessarily comprehensive or accurate.