Equity Stake The part of a company that a person owns. Example, when someone wants to own a part of someone else's company they have an equity stake; a percentage.
Valuation An estimation of what something is worth. Example; when you own a business it has a valuation based on how many people buy the product and what your profit is.
Investment The action of paying money into a business to receive a profit. Example; you would invest in a business to get more money then you put into it.
Advisory Board A body that provides advice to manage a corporation. Example; this would help you in a business to see what decision to make and have some perspective on how to run your company.
Perpetuity Something that lasts forever. Example; by creating a company that can people will like the product for generations is something that is perpetuity.