Age Up is a group of ongoing (as of March 21, 2013) changes that includes more freedom for users who are 13 years or older. The update focuses mainly on benefitting the older players who would play on ROBLOX and the segregation of young players away from the older players in order to allow the older users to feel comfortable with other users who are 13 years or older.
Despite controversy among many ROBLOX users regarding the update and age restrictions, there is much support by many users for some of the promised updates that are aimed for older players, such as advanced Role Playing Games, Call of Duty fanboy market, and other updates that are provided and aimed for users who are 13 years or older. Other possible additions include improvements in gameplay, such as the ability to import other sounds and music from other sources and better ease of use on scripting, and segregation between young and old users.
So far, as of today, not much changes that associate with said update have been made, although the genres, FPS and RPG, have already been added, possibly being associated with the update. Scary was renamed to Horror in possible association with the update. War was also renamed to Military.
Also, users, if creating an account, can attempt to set their birthdate so that they can be seen as being 13 years or older, therefore the update can be rather annoying, as users who are actually 12 years or under can easily fabricate a 13+ account so that they can receive the benefits that users 13 years or older would normally get while being actually below the age at the same time.
Various gears, which are realistic ranged firearms, had been released with the 13+ icon as a part of the "Age Up" updates, including, but not limited to: the Trench Warfare Shotgun, the M1 Garand, and the Luger Pistol. What most of the available 13+ gears have in common are that they are actual World War II-era weapons.