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MoneyMolecule$MoneyMolecule
The Money Translator

Every confusing money word,
in plain English.

The finance industry hides simple ideas behind intimidating words. Here’s the whole vocabulary, decoded — search it, or browse by topic.

Concepts worth seeing

A few ideas land better as a picture than a paragraph. Scroll the cards — they animate.

Banking & credit

Compound interest

Interest earning interest. APR is just the rate; APY is the rate after compounding — which is why your balance curves upward instead of climbing in a straight line.
Yr 1Yr 20↑ snowballs
Funds & fees

Expense ratio

The yearly % a fund quietly skims from your money. 1% sounds like nothing — but over 30 years it can swallow a six-figure chunk of your gains.
0.05% fee1% feegap = lost to fees
Investing

CAGR

Compound Annual Growth Rate: the one smooth yearly rate that gets you from your starting value to your ending value — it cuts through the bumpy up-and-down years into a single honest number.
smooth CAGRactual (bumpy)
Funds & fees

AUM

Assets Under Management — the total pile of money a fund or advisor looks after. Their fee is a slice of that pile, which is how a “small” 1% turns into enormous revenue.
$2.4BAUM1% fee= $24M / yearA tiny slice of ahuge pile is stilla fortune.
Investing

Diversification

Not putting all your eggs in one basket. Spreading money across many investments so a single bad one can't sink you. A typical mix might look like this.
Stocks · 60%Bonds · 25%International · 10%Cash · 5%
Banking & credit

Credit utilization

How much of your credit limit you're using right now. Keeping it under about 30% helps your credit score; running it near the max quietly drags the score down.
30% lineHealthy zoneMaxed = score drops
Loans & mortgages

Amortization

Your loan payment stays the same each month, but the split shifts: early on you're paying mostly interest, and only later mostly principal. That's why extra payments made early save you the most.
InterestPrincipalLoan startPaid off
Taxes

Marginal vs. effective rate

Moving into a higher tax bracket only taxes the income above the line at the higher rate — not your whole paycheck. Your real, blended average (the effective rate) is almost always lower than your top bracket.
0%
12%
22%
24%
Effective ~14% · your blended averageMarginal 24% · only your last dollars
Funds & fees

ETF vs. mutual fund

Both are baskets holding many investments at once. The differences are how you buy them and what they cost — and those differences usually favour the ETF.
ETF
Mutual fund
TradesAnytime, like a stockOnce a dayTypical feesVery lowOften higherTo start1 shareSometimes $1k+
Insurance

Deductible → coinsurance → OOP max

Health insurance shares costs in three stages as your bills add up: first you pay everything (the deductible), then you split it (coinsurance), and once you hit your out-of-pocket maximum, the insurer covers 100%.
Your medical costs over the year →
You pay all
You pay a share
Insurer pays all
DeductibleCoinsuranceOut-of-pocket max

Spot a term we’re missing? Email info@moneymolecule.com and we’ll add it. Definitions are written for clarity first, not for lawyers.