To my knowledge

Sales Record:

A document used internally as a record of sold items.  This include the item description; price; stock number and other related information.

Advantage:

Include a simple description of each item:

Helps the business to know more about each item and to provide information to customers.

A clear stock number of each item/task.

Help managing the stock number:

A computerised sales record can help managing the stock number.  Ie when an item sold through the computer system (scanned bar code etc), the stock number is automatically reduced.  When the stock number reached a set low point, the system will contact the wholesaler and to order the next stock automatically.  This system is used widely in supermarkets.

Addition information of the item/task.

Disadvantage:

Record needs to be updated very frequently to keep the correctness high:

If the record is not up-to-date, the stock number; the information and other additional

Document only used internaly with the business. Customers do not have access.