"Pattern matching" is what regular expressions do. What you are alluding to is "pattern recognition", which is an older name for so-called "statistical" machine

"Pattern matching" is what regular expressions do. What you are alluding to is "pattern recognition", which is an older name for so-called "statistical" machine learning, particularly used to perform "perception" tasks (such as machine vision). "Statistical" machine learning is also not very much about statistics, it's just that similar technologies and concepts are sometimes used as in statistics, for example probabilities, function optimisation etc. "Artificial Intelligence" (AI) is the name of the field of research that studies approaches to artificial intelligence. It's a bit confusing but when someone says "I study AI" they don't, today, mean that they study artificially intelligent entities, rather they mean they study approaches that might one day allow us to create such entities.