What 2 processes spread agriculture around the world?

The 2 process that spread agriculture around the world are: 1.) Diffusion 2.) Slow colonization or migration of agricultural people (growing populations pushed them outward).

Difussion happens when a social group started to spread innovative idea among its members (such as agricultural technology)

Slow colonization happens when a social group tried to maintain activity that always been done in the past (such as gathering and agriculture)