C++20 brings significant changes, including the three-way comparison operator (Spaceship Operator), which provides new functionality and allows for the synthesis of relational operators. The C++20 standard also introduces improvements to generic lambdas, function template parameters, and library features that help navigate undefined behavior. New tools like span handle variations on passing vectors with non-const pointers to functions that take const pointers as arguments, making code cleaner and more efficient. Additionally, C++20 includes new string methods (`starts_with` and `ends_with`) and improved error handling mechanisms, such as the erase-remove idiom and its replacement with `std::erase`. The analyzer can guide developers through many of these changes, suggesting improvements to make their code safer, easier, and more performant.