Pos tagging indicates the property of the word itself.
Dependency tagging indicates the function (or relative information) of the word.
Both N-gram model and PCFG model assumes the a Markov property and then applies the conditional probability.
Dependency Grammar Notions
subject: The person or thing about whom the statement is made
predicate: The purpose of the predicate is to complete an idea about the subject
Part of Speech Tagging
Local Preference -> The probability of a part-of-speech tag for a specific word in the vocabulary
Contextual Preference -> The probability of a part-of-speech tag for a specific word in given context.