The fillet command creates a rounded edge between two objects.

1) Activate the fillet command by selecting the Fillet button OR by typing in "fillet" and hitting enter

2) Specify first object

3) Select Radius

4) Specify radius

5) Specify second object

The chamfer command creates a straight edge between two objects.

1) Activate the chamfer command by selecting the Chamfer button OR by typing in "chamfer" and hitting enter

2) Specify first object

3) Select Distance

4) Specify first distance (distance from corner to first object)

5) Specify second distance (distance from corner to second object)

5) Specify second object