What's the difference between "branch" and "leaf"?

[Gokudo01]

I can't catch the slight difference between those two agreements :

National Science Foundation: Science cost for branch techs reduced by 6 / 8 / 10% [150 + 15 DC/T]

AND

Scientific Grant Program: Science cost of Leaf technologies are reduced by 6 / 8 / 10%. [150 + 15 DC/T]

May anybody help me ?

 

[Roxlimn]

Branch technologies are the ones appearing with lines to and from other nodes. An example is Robotics. Leaf technologies are the techs within each node. An example is Servomachinery.

 

[Gokudo01]

thanks sir