A civil war is, simply put, a war between citizens of the same country. Be it a division that falls along political, racial, gender, geographic region, or any other lines, if it is involves citizens of the same country who are at war with each other it is classified as a civil war. Civil Wars generally are fought for political independence (or dominance) of each side - they may or may not result in a splitting of the original country, but those wars where secession is a stated goal of one side (not just an outcome) are generally always considered a Civil War.

A revolution is a war fought to overthrow or rid yourself of a government in order to establish a new one. The old government may be indigenous, or may be external (i.e. colonial). In general, the main point of a revolution is to completely overthrow the existing government and replace it with a native government, NOT to split the country. Revolutions can be civil wars, but civil wars do not have to be revolutions

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