Research is an effective way to permanantly buff your city in various ways. Research can affect everything from resource generation of all types to increasing the amount of secure storage and even increasing your combat potential and efficiency. All research is conducted in your city's Institute.
There are 7* different research trees consisting of 3 general categories, Basic, Troop transport, and Troop upgrades. The basic category has 2 subcategories consisting of Military tech and Production Tech that enhance the primary aspects of their affected game elements. The production tech has 2 trees, one affecting output as a whole and the other tree affecting Rapid Resource production. The Troop Transport Tree may have multiple trees based on the number of Barracks you have however each tree has the same technology set.
Each Research tree has various technologies that can be achieved. Each research also has a level. Some researches can only be researched once while others have up to 20 levels for a single technology. Much like building the city itself you must expend various resources and money for each research you complete. In total there are over 900 levels of technology to research.
You may only research 1 technology at a time.
The Research Trees are as follows: