>Skwerl りす-san As Shihei-san & tokyo-03 san mentioned, 「そっか(sokka)」is from 「そうか(souka)」. Sokka is much more casual, shortened and conversational version of Souka. Sou-desu-ka is for polite and formal situation.

Yep, "sou (desu) ka" it is. 'Sokka', for short. The 'ka' particle isn't really meant to make it a question, btw. It's like the German: "Ach so!?" Hence, when I encounter "Sou ka!" in Anime, I translate internally to "I see!" (which is pretty much short for "O, it's like that?! I see!"). There's a built-in realization moment, as it were, followed by the statement that you (now) understand. It's not just the same as wakarimasu! (also "I understand")

Hi, 「そっか(sokka)」 is from 「そうか(so-ka)」 as Cherry said. It's 「そう + か」. 「そう( so- )」 basically represents things that comes before. In English, it looks like [it] or [that] [so]. for example. [I think so]. Same pronounce, it's by chance :D [そう] is often used in conversation. I hope you understand what I wanted to say. If you have more questions, contact me anytime !

Hello Tsukinowa, "Sokka" comes from the Japanese phrase "So Ka" which means "I Understand." It was used in Avatar: The Last Airbender for a main character.

Skwer, now that I've learned hiragana (can you tell I'm proud? LOL), I think the 'tsu' in そっか (sotsuka) is just a way to form the double 'k'. So it really just says 'sokka', after all.