AAT Level 2 Introduction to Bookkeeping: Confused over information in Textbook

evegeog

I have just started my self study course with First Intuition and I am struggling to understand something that is in the Introduction to Bookkeeping course. In the very opening section it is explaining what various key documents are and provides examples. One such example is that of a Sales Order. The textbook says "If the quote is acceptable to [the buyer], then their purchase department will raise an order and send it to [the seller]. This will be a Sales Order for [the seller]." The example shown then illustrates a Sales Order sent from [the buyer] to [the seller]. From my understanding, this is incorrect. I thought the purchase document sent from the buyer should be a Purchase Order, and the internal document produced by the seller would be a Sales Order. Am I incorrect or is this textbook wrong? I've tried to look online but its only left me even more confused.