What is the difference between informal and formal amendment?

The difference between informal and formal amendment is that, the informal amendment does not actually change the Constitution itself. While formal amendment has a impact in the constitution.

the protestant reformation's started in 1517, disturbing the religious and political order in europe´s catholic countries. the outcome was the european wars of religion prosecuted in europe in the 16th, 17th and part of the 18th century. nonetheless, uprisings, territorial disputes, and great power conflicts were also causes of the wars.  

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