Lookup/Select contains various ways to lookup an item. (example:  Customer Number, Account Number, Part Number).

Entry Options contains various things you may do at "Enter Selection" such as:  Edit, Save or Delete.

Markup Percentage Table consists of the following: Formula for calculating Percentages based on Gross Profit. List of most commonly used Markup Percentages based on Gross Profit.

How Customers are Taxed consists of various setups in Accounts Receivable and Inventory.

Customer Credit Limit Check explains how it works and where to find the associated setups.