From the website:
DeKalb County operates under the township form of County Government. The governing body is the County Board. As the legislative element, the County Board is responsible for adopting all Ordinances for the governance of DeKalb County, which laws are contained in the DeKalb County Code establishing budget for several funds as well as levying taxes, promulgating policies, rules and regulations for the management of County operations. The County is divided into twelve 12 Districts based on population. Members are elected for 4 year terms. One member is elected in each District every 2 years.