I have seen several blend node

there are:

1:blending value is closed to input1 ,connect input1 .

2:blending value is closed to input1,connect input2

3:blending value is closed to input1,connect both input1 and 2

4:blending value is closed to input2,connect input2

5:blendind value is closed to input2,connect input1

6:blending value is closed to input1 and 2

7:blending value is closed to input1 or 2,no connecting input1 and2

Sometimes blending is connecting image or other nodes,or no connecting nodes

above all,

Connect what is by blending value is what?

Or,it is by what material should be done?

 

For any easy sample to demo?