In Illinois the executive branch consists of the five elected constitutional officers.
Many publications including The Illinois Blue Book and the Illinois Handbook of Government are excellent resources and include photos of constitutional officers, agency heads and many other facts and details that are valuable to better understanding the seemingly complex thing that is the State of Illinois.
The Governor is the head of state in Illinois. The Governor and Lieutenant Governor are elected in tandem in both their primary and general elections. The Lt. Governor has few details spelled out in the job description, with their job to fill the vacancy of Governor, as in the case when Rod Blajogevich was removed from office and Lt. Governor Pat Quinn assumed the job.
Briefly here are quick descriptions of the other posts.
Attorney General– The Attorney General shall be the legal officer of the State, and shall have the duties and powers that may be prescribed by law. The Attorney General represents the people of Illinois in cases against the state and can sue on behalf of the state.
Secretary of State-In Illinois, the Secretary of State oversees the motor vehicle operations and drivers license registration among the other duties. The Secretary of State shall maintain the official records of the acts of the General Assembly and such official records of the Executive Branch as provided by law. Such official records shall be available for inspection by the public.
Treasurer-The Treasurer’s job is to invest and keep the state’s money.
Comptroller-Is the accountant and and determines what bills are paid.