Hello DankMemes322
Example #1: Guns, weapons, and explosives were not new, but they became much more reliable.
Example #2: Aircraft and balloons where used to observe the battles and to directed artillery. Aircrafts used to be unable to be used in this matter, but got improved during WWII.
Example #3: Gas masks where commonly used during WWII and where mandatory for survival, since poison gas was a common way to kill in the trenches.
Hope This Helps You
-Chris