Battlestars are giant space going leviathans ranging form almost 700m to nearly 2.3km in lenght. A Battlestar is divided into 5 sections, first the "alligator head" at the front of the ship, this houses the CIC along with large amounts of sensor equipment and the much of the Battlestar's offensive capability. Second is the body of the ship this houses the primary storage, causeways linking parts of the ship and on most classes large KEW cannons. Third is the engine section, this houses the primary sublight and the FTL drives of the ship. Last is the two flight pods, these house the hangers, viper launch tubes and in many classes more KEW weapons.
The term "Battlestar" had been in use in the 12 colonies for years prior to the Cylon War. However, its use was not consistent, being used for all types of large command/or frontline ship (much like the designation "Capital ship" in Earthly navy's). It wasn't until the years leading to the Cylon War that the modern Battlestar, a carrier/battleship with a pair of flight pods, was developed. In the years leading up to the war the military power of the strongest colonies was almost completely in the hands of the cylons. Fearing the possibility of any cylon "Malfunctions" two classes of Battlestar were developed as a safe guard, the advanced Ares class and the primitive Jupiter class. Built for the inter Colonial government, officially intended to act as a peace keeping force, Twenty Four ships were planed. Twelve of each class. The first to be built was the Battlestar Ares, a Ares class. It was shortly joined a further two of it's class, and the original Jupiter class ships. However a year after the construction of the Ares the 1st Cylon War broke out. At this point the colonials committed to a fleet of 12 Jupiter class Battlestars specificaly desingned to resist Cylon computer infiltration. These ships had infact been built because the colonial government secretly suspected that the Cylons would rebel and wanted a safe guard for when and if they did. These ships became famous for there role in the war and are commonly refered to as the original battlestars. Since the Cylon war many more Battlestars have been built and at the time of the attacks the Colonial fleet consisted of around 120 battlestars. After the attacks only around 7 Battlestars are known to have Suvived.