Techs allow you to produce more goods, build new structures, and move forward through the ages.
To research and unlock new techs, you need to spend knowledge points in the tech panel.
You earn knowledge points when doing actions such as hunting animals, gathering resources, or achieving higher populations.
You can only unlock a tech if you have previously unlocked its prerequisite techs and the era it belongs to.
To unlock a new Era, you need to unlock its Era Tech, which requires twice as many Knowledge points to unlock.