This document provides an overview of transgenic or genetically modified foods. It discusses how genetic engineering is used to introduce new genes into plants, crops, and animals to improve traits like disease resistance, growth rate, and nutritional content. Both advantages and risks of GM foods are outlined, such as increased production but also possible contamination and loss of biodiversity. The situations regarding GM foods in the United States, Europe, Spain, and Catalonia are briefly summarized. The United States largely embraces GM crops while Europe takes a more cautious approach with strict regulations. Spain and Catalonia have significant GM crop cultivation within Europe.