The Addenda is a complement to the CFDI, it is used to specify the commercial information that is being handled. It is an optional element that is taken into consideration, it may or may not be added to the tax receipt, its function is to deepen the non-fiscal information.
If you decide to use it, it must be included in the XML format to specify non-fiscal information, according to the commercial practices that are being carried out at that moment. Some of the data that are usually included are the purchase order, supplier identification, delivery of goods, among others.
The Sales Glossary is a compendium of all the most commonly used terminology in sales strategy. Many of the concepts listed here are used when implementing a CRM system or a digital sales funnel, no matter if they are legacy systems or an online CRM. See also our blog that deals with sales techniques, marketing and sales culture.