WWI was b/n 1914-1918 and is one of the major military confrontation of the 20th Century
The war was considered as a global war
There were about 30 countries involved in the continents of Asia, Africa, Europe, and North America
The immediate cause for the outbreak of WWI was the assassination of Archduke Franz Ferdinand of Austria-Hungary on June 28 1914 by a Serbian nationalist Gavrilo Principle
