For instance, seaweed is alga marina in most Spanish-speaking nations, while in Chile we use the native cochayuyo for edible seaweed. While for the most part differences in vocabulary simply give rise to a little humor, once in a while they can give offense. Most native speakers know to adjust their understanding and use of vocabulary accordingly. Differences between Spanish-speaking nations are underscored when slang is used, and minimized when a more formal Spanish is utilized. Differences in accents are much more pronounced than divergence in vocabulary.
Accents are easy to pin down, however.
I was speaking to someone in English and an observer who overhead the conversation asked if I was Chilean, just from the way I spoke English. I am asked this question often. The Spanish spoken by native Mexicans is beautiful. Sometimes second generation speakers will make up their own vocabulary as they go. For instance, instead of saying freno for the word brake, they may use breka.