Phonetics is the branch of linguistics which studies the characteristics of speech sounds.
Phonology is the branch of linguistics that studies the patterning of speech sounds in languages.
Morphology is the branch of linguistics which studies the structure of words and types of their formation.
Syntax is the branch of linguistics that studies sentence structure.
Semantics is the branch of linguistics that studies meaning in language.
Sociolinguistics is a study of language in social contexts.