Investment Basics Cheat Sheet

Investment basics for beginners — stocks, bonds, ETFs, index funds, dollar-cost averaging, risk tolerance, and building a simple, diversified portfolio.

Last Updated: July 15, 2025

Investment Vehicles

TypeWhat It IsRisk
StocksOwnership in a company — price rises/falls with performanceHigh
BondsLoan to government/corporation — fixed interest paymentsLow
ETFsBasket of stocks/bonds traded like a stock — instant diversificationVaries
Index FundsTrack a market index (S&P 500) — low fees, broad exposureMedium
Mutual FundsActively managed pool of investments — higher fees than ETFsVaries

Key Principles

PrincipleWhat It Means
Dollar-Cost AveragingInvest fixed amount regularly — buy more when cheap, less when expensive
DiversificationDon't put all eggs in one basket — spread across sectors, geographies
Compound InterestReturns earn returns — $10K at 7% for 30 years = $76K (without adding a dime)
Time in Market > TimingMissing the 10 best days in 20 years cuts returns in half

Simple Portfolio (by Age)

AgeStocksBonds
20s-30s90%10%
40s80%20%
50s70%30%
60s+60%40%

Tax-Advantaged Accounts

AccountTax Treatment
401(k)Pre-tax contributions, tax-deferred growth, taxed on withdrawal
Roth IRAAfter-tax contributions, tax-free growth, tax-free withdrawal (after 59½)
HSATriple tax advantage: pre-tax in, tax-free growth, tax-free out (medical)
Pro Tip: The best investment strategy is the one you'll stick with. A simple two-fund portfolio (Total US Stock Market + Total Bond Market) beats 80% of professional fund managers over 10 years. Complexity is the enemy of consistency.
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