DCF and NPV are present-value tools
DCF values expected future free cash flows. NPV compares the present value of benefits with the present value of costs.
CAPM estimates required equity return
The basic CAPM formula adds the risk-free rate to beta multiplied by the market risk premium. It focuses on systematic risk.
WACC blends capital costs
WACC combines the cost of equity and after-tax cost of debt using capital-structure weights. It is often used for FCFF valuation.
Ratios need interpretation, not memorization
Current ratio, ROIC, EBITDA margin, leverage, and turnover ratios only become useful when compared with industry, history, and business model.