* Likely origin: It's thought to be a playful combination of "okay" and "dokey" (meaning "ready" or "agreed").
* Popularity: It was popularized in the 1930s and 40s, especially among children and young adults. It was often used in comic strips and radio programs.
* Variations: "Okie dokie" and "okie doke" are also common variations.
* Modern usage: While less common today, it's still used playfully in casual conversation.
It's important to note that its origin is not definitively known, and there are other theories out there.