First of all, you should be posting these in a different forum, like "Learning Japanese." Second of all, why didn't you just search for it at the same site, like this.
An origin of Pocky of chocolate
From a homepage of Ezaki Glico なぜ？なに？コーナー | 【公式】グリコ
A literal translation
I parody "a chocolate stick" at first
There was you as "chocolate Tettuku" in a meaning of a chocolate snack to eat in spite of being a walk.
I became "the Pocky chocolate" which had a sound of "POTTUKIN" when I did a sale experimentally afterwards.