You can access the Research Tree through the Main Menu.
It is filled with different types of technologies. They can unlock upgrades for existing buildings, completely new buildings, new units in the Barracks, additional expansions, increase your squad size, or unlock a production boost.
This is the main way to measure your progress in Elvenar. These technologies are linked together and many build upon each other, but you still have some freedom to choose in which order you research them.
To be able to research a technology, you need to activate all dependent previous technologies. After that, you can unlock it with Knowledge Points (KP) and activate it with Coins and/or supplies and/or Goods.
Knowledge Points (KP) generate automatically over time. If you wish, you can buy them with Premium or with Coins. You can fill the KP bar partially (smallest amount is 1), until the demanded amount is reached.
In contrast to this, the resources for activating technologies cannot be partially paid. Only when all the required resources are available, will you be in a position to activate it.
On the other hand, If you are missing some resources, you can use Premium to buy them instantly.This, will also automatically unlock the technology. Additionally, you can use Premium to instantly unlock technologies in the Research Tree.
Note: The Premium used to unlock the technologies will take into account the resources you have. This means that if you still have Coins, Supplies or Goods, it will use them first, and then use diamonds for the missing ones.