Think like an owner

A share is a claim on a business

Imagine a neighbor runs a small maintenance company. She fixes pumps and boilers for the apartment buildings on your street, and she offers to sell you a tenth of the business. Before you discussed a price, you would ask what she sells, who pays her, what it costs to operate, and how much cash remains after keeping her van and tools in good condition. You would want to know whether her biggest customer can leave tomorrow and whether her bank loan comes due next month. You would not ask what the business was "worth last Tuesday".

A stock deserves exactly the same questions. A share is one equal unit of ownership in a company. Owning it gives you a proportional claim on the company's future profits, its cash and its assets, after the company's obligations to lenders, suppliers, employees and tax authorities have been met. The ticker, the short code a stock trades under, makes ownership easier to trade; it does not remove the economics underneath it. The price on your screen changes every few seconds. The business underneath changes much more slowly.

Fundamental research is the process of connecting those economics to the price of the ownership claim. You study the business, test the reported numbers, estimate a range of possible outcomes, and decide whether the price compensates for uncertainty. This course gives you a first research process for ordinary US operating companies. Banks, insurers, REITs, and early-stage biotechnology businesses need additional industry-specific tools. You do not need to force every company through the same spreadsheet.