Both have a role to paly in the sales documentation .

Item category group refers to the material type and to

which material charecteristics does this belong and is

configured in MM02 in basic data 1 tab where as Item

category group is from the sales porspective which is

defined in sales org 1 tab or in vov7

Based on the Genral Item category group one can define

the item category group

Eg : In the general Item Category goup is given as BANS

then the item category group is TAS AND IN Sales docment we

can clearly understand that that the line item material

belongs to Third party and should have a purchase

requisation created for this in schdule lines

Similaryly if the Genaral Item Category Group is given as

ERLA then the corresponding item category group is TAQ

which refers that this line item will have set of

components associated and has pricing associated