There are 6 keyword match types in search advertising: broad, phrase, exact, broad match modifier, negative, and embedded. Broad is the most expansive while exact only matches the keyword verbatim. Phrase falls between broad and exact by matching keywords in the same order. Broad match modifier (indicated with "+") functions like broad but clicks don't contribute to quality score. Negative (indicated with "-") removes clicks for that keyword. Embedded uses a negative modifier with another match type. There are also different ad formats and best practices for writing compelling text ads.