In Japan, people call the pickled ginger Gari (ガリ) or Shin-shoga no Amazu-zuke (新生姜の甘酢漬け).
It’s young pickled ginger that is soaked in sweet vinegar brine. It can have a blush pink color when made from young ginger or artificially colored, or beige if made by regular ginger.
Pickled sushi ginger is often served and eaten while you eat sushi and it’s an essential part of a sushi meal. The spiciness and sweet vinegar flavor of the ginger help cleanse the palate between eating, allowing you to enjoy different pieces of fish and rolls. The name Gari is said to be from the onomatopoeia of the crunching noise or the sound of a knife thinly slice the ginger. At a sushi restaurant, you can ask more gari if you want extra.
There are many types of pickles or what we call Tsukemono (漬け物) in Japan. The sweet and vinegar type is called Amazu-zuke (甘酢漬け).