List methods and functions: append(), insert(), index(), remove(), sort(), len(), sorted(), del

Lists come with methods, which you call with dot notation on the list itself (lst.append(4)), and they also work with general built-in functions such as len() and sorted() and with the del statement. The difference matters on the exam: methods like append() and sort() change the list in place and return None, while functions like sorted() leave the list alone and return something new. Knowing which tool mutates and which returns a value is the key to predicting output.