What is Bootstrap CSS?
Bootstrap Commonly abbreviated to "Bootstrap," CSS is a widely-used open-source front-end framework built for creating sites and apps that are mobile-friendly and responsive by default. Bootstrap, which was first developed by Twitter, has become a popular and effective tool for web developers because to its intuitive interface and huge library of pre-designed components and styles.
As of my most recent check in September 2021, Bootstrap 5 is the most recent available version. When compared to its predecessor, Bootstrap 4, it had several modifications and enhancements.