Shoshinsha mark
The Shoshinsha mark (初心者マーク) or Wakaba mark (若葉マーク), introduced in 1972, is a green and yellow V-shaped symbol that new Japanese drivers must display on their cars for one year. A driver must display this mark on the front and back of the car for one year after they obtain a standard driver's licence. This obligation is only for a standard license, not for motorcycles, large vehicles, special cars and so on. Drivers who consider themselves beginners may continue to display the sign, even after the period of a year.
Its official name is The Beginner Drivers' Sign (初心運転者標識 shoshin untensha hyōshiki). Conversely, the orange and yellow "Fukushi mark" or "Koreisha mark" denotes elderly drivers. Both marks are designed to warn other drivers that the marked driver is not very skilled, either due to inexperience or old age.
Other uses
The Shoshinsha mark is commonly seen on topics/tutorials targeted at beginners (whether it involves driving or not), having the meaning "For beginners" or "Beginners are welcomed" .
The mark is also used as the logo for the imageboard software Wakaba written in Perl by Turku, Finland-based programmer Dag Ågren and by the imageboard index iichan whose indexed imageboards use Wakaba as their software package. The software also features a markup language called Wakabamark.
The mark is also increasingly being used by JDM enthusiasts in other countries, such as Australia, Malaysia, Malta, New Zealand, the U.K and U.S.A. to show their passion and interest in JDM culture. Some have taken the Shoshinsha shape and replaced the original green and yellow colors with their own flag to distance themselves from the "beginner" label, while still showing their enthusiasm for JDM car culture. There are even sites specializing in producing these "custom" wakaba badges. Thus, in countries besides Japan, the Shoshinsha mark has become more of a decorative decal rather than a traffic warning.
The mark is represented in Unicode as U+1F530 (🔰).