Reform means the improvement or amendment of what is wrong, corrupt, unsatisfactory, etc. The use of the word in this way emerges in the late 1700’s and is believed to originate from Christopher Wyvill’s Association movement which identified “Parliamentary Reform” as its primary aim. 
Reform is generally distinguished from revolution. The latter means basic or radical change; whereas reform may be no more than fine tuning, or at most redressing serious wrongs without altering the fundamentals of the system. Reform seeks to improve the system as it stands, never to overthrow it wholesale. Radicals on the other hand, seek to improve the system, but try to overthrow whether it be the government or a group of people themselves.
Developing countries may carry out a wide range of reforms to improve their living standards, often with support from international financial institutions and aid agencies. This can include reforms to macroeconomic policy, the civil service, and public financial management.
A note about spelling: when used to describe something which is physically formed again, such as re-casting it in a mold/mould, or a band that gets back together, the proper term is re-form (with a hyphen), not "reform".
- dictionary definition http://dictionary.reference.com/browse/reform?s=t
- Reform in English Public Life: the fortunes of a word. Joanna Innes 2003
- On term limits reform see, U.S. Term Limits. On more radical/revolutionary changes, including term limits, see, for example, Robert Struble, Jr., Treatise on Twelve Lights: To Restore America the Beautiful under God and the Written Constitution, 2007-08 edition.