## TL;DR

The Time Value of Money (TVM) is the core principle of finance: a dollar today is worth more than a dollar tomorrow because it can be invested and earn returns. Key concepts: present value (PV), future value (FV), discount rate, compound interest, net present value (NPV). NPV > 0 means investment creates value.

## Core Explanation

FV = PV × (1 + r)^n. At 7% return, money doubles every ~10 years (Rule of 72: 72 ÷ 7 ≈ 10.3). Discounting: PV = FV / (1 + r)^n — reverses compounding. Annuities: equal payments over time. Perpetuity: infinite payments — PV = payment / rate. Opportunity cost: next best alternative foregone. Risk-adjusted discount rate: higher risk = higher rate = lower PV.

## Further Reading

- [Principles of Corporate Finance (Brealey, Myers, Allen, 14th Ed)](https://www.mheducation.com/highered/product/principles-corporate-finance-brealey-myers/M9781264080946.html)