Languages change over time. I am wondering if there are certain features that are consistently more stable (i.e. changing more slowly) than others, and if yes, what are some examples?
There are many different features of languages that change, such as vocabulary used for certain categories, phonological features, grammatical features, etc. Are there some of these which appear to be resistant to change, and tend to be inherited from the language's ancestor? Are there some which are more commonly borrowed from (or shared among) neighbouring languages? Are there some which tend to evolve rapidly even without external influence?
In comparative linguistics, does a commonality in some types of features carry more weight as evidence of shared ancestry then others? If yes, which features are considered the most stable/unstable?
Potential examples: Vocabulary: Do the names of numbers change faster or slower than other vocabulary categories? Phonology: Do vowels tend to mutate into unrecognizable forms more rapidly than consonants?
Both direct answers and recommendations for further reading are welcome. Please write your answers for laymen, if possible. I assume this question must have been studied extensively already, but having no background in linguistics, I was unable to find much. I probably do not know the correct keywords to search for.