What is the difference between Move & assign statement?

MOVE <f1> TO <f2>.
To assign the value of a data object <f1> to a variable <f2> or the equivalent statement
<f2> = <f1>.
The contents of <f1> remain unchanged. <f1> does not have to be a variable - it can also be a literal, a text symbol, or a constant. You must always specify decimal points with a period (.), regardless of the user’s personal settings.
Multiple value assignments in the form
<f4> = <f3> = <f2> = <f1>.

ASSIGN <f> TO <FS>.
When you assign the data object, the system checks whether the technical attributes of the data object <f> correspond to any type specifications for the field symbol <FS>. The field symbol adopts any generic attributes of <f> that are not contained in its own type specification. Following the assignment, it points to <f> in memory.