Answer:
World War One was a war in which people began to use modern technologies and expand their strategies on how to use said technologies in warfare, while World War Two is where they were advanced and utilized said modern technologies in a much more practiced and streamlined fashion.
Explanation: Differences: A couple of examples for WWI would be tanks and airplanes. Tanks were only used halfway into WWI and were not efficiently produced at the time. Tanks at the time were also not as useful as they are today, getting stuck much more often. Airplanes were also in early development during WWI, and they were mainly used for reconnaissance due to the abundance of trench warfare. WWII changed a lot of these things. Once WWII started, tanks had been advanced much further and a new tactic had been invented by the Germans; The Blitzkrieg. The Blitzkrieg was reliant on the use of light tanks and aircraft due to the whole tactic revolving around the factor of speed. The Germans thought the quicker they could take down their target before they got prepared, the better, therefore faster tanks were created. Tanks were also much more used and produced during these times. Planes were also being used extremely often, being used for bombing much more often due to them being able to go higher and with more accuracy.
Similarites: World War One and Two were very similar in the fact that each side of the war advanced modern technologies far and quickly during the war. Each side also utilized tanks in both wars, as well.