Furisode is a light-weight formal kimono that features long, flowing sleeves. It is an extremely beautiful and formal kimono that is first worn on comming of Age Day and is also worn for formal functions like weddings. It is worn by young unmarried women. THe furisode sleeves are traditionally considered to be flurtatious and attract young single men. Just FYI, the long sleeves are not only beautiful, they're traditionally a sign of availability.
Kakeshita is a special type of bridal furisode that is worn under a shiromuku-uchikake or iro-uchikake. The kakeshita features 42" long sleeves. and a double padded hem. It is still lighter than a shiromuku or iro-uchikake.