My mother tongue is Argentine. Many will say that it is Spanish or even Castillan, but if you pay close attention, you will discover that, although we can understand each other quite well, not all Hispanics speak the same language. Argentines, as well as Uruguayans, are known for pronouncing the letter "elle" or "double l" that you can find in the word "llave" (key) with a "sh" sound, as you would say in English the word show.
During my years at the university in the US I had many Spanish-speaking colleagues from different places: Zulma and Natalia from Puerto Rico and Maricel from Peru were the ones with whom we had the most conversations on this topic. They always laughed at my "voseo" (treating people with the "vos" form instead of the "tu" form as almost all Spanish-speaking countries do) but also my "ll" and a whole series of words that we use in very different way.
A story that I will never forget was when Zulma asked me where I had bought the "pantallas" (screens) I had on: "pantallas"? I said. The one on the TV or the one on the computer, I thought? But she was actually referring to my "aros" (earrings) that in Puerto Rico are called "pantallas". It's only been about 15 years from that conversation but every time it goes through my head I can't stop laughing.