You're looking at a list of funds and none of the words mean anything

Diversification, which is the only free lunch

Owning one company means your money depends on that company. It can be run badly, sued, disrupted, or simply unlucky. Owning hundreds means no single failure matters much.

That is diversification, and it is unusual because it reduces risk without reducing expected return. Almost nothing else in finance does both.

The failure it prevents is concrete. People put everything into the company they work for, because it feels familiar. Then the company has a bad year, and they lose the job and the savings in the same month. Section 22 covers why your employer’s stock is the worst place to concentrate.

It also applies across kinds of things, not just across companies. Stocks, bonds and cash behave differently in a bad year, which is why owning some of each smooths the ride.

A single broad index fund gives you diversification across companies in one purchase. That is the whole reason it is the standard answer.

Index funds, mutual funds and ETFs, in plain terms

These three words describe different things, and people use them as if they were alternatives to each other. They are not.

A mutual fund is a structure: a pool of money from many people, invested together, managed by a company. It prices once a day, after the market closes, and you buy in dollar amounts.

An ETF, or exchange-traded fund, is also a pool — but it trades on an exchange like a share does, priced continuously through the day. Most brokerages now let you buy fractional shares, so the old advantage of mutual funds accepting any dollar amount has largely gone.

Index fund describes the strategy rather than the wrapper. It means the fund simply holds everything in a defined list — an index — rather than paying someone to pick winners. You can buy an index fund as a mutual fund or as an ETF. Both exist, and for a long-term investor the difference barely matters.

The word that does matter is the opposite of index: actively managed. That means a manager choosing investments, and charging you considerably more to do it. Decades of evidence say most of them do not beat the index they are trying to beat, especially after their fees.

The scorecard that tracks this is S&P Dow Jones Indices’ SPIVA report. In 2025, 79% of actively managed U.S. large-company stock funds underperformed the S&P 500. Over fifteen years, 89.93% did. The longer you hold, the worse the odds of having picked a manager who beats a plain index fund — and the fees are charged every year regardless.

So the practical translation: index is the thing to look for, mutual fund or ETF is the packaging, and actively managed is the thing to look at twice before buying.

What fees actually cost you

Every fund charges an expense ratio, expressed as a percentage taken annually from whatever you have invested. It is deducted automatically whether the fund goes up or down, and you will never see it as a charge on a statement.

The numbers look tiny and are not. Broad index funds commonly charge somewhere around 0.03% to 0.10%. Actively managed funds often charge 0.50% to 1.00% or more.

Run that difference over a working life and it is the largest single controllable cost in your investing. Contributing $300 a month for forty years at a 7% return, the difference between paying 0.05% and paying 1.00% comes to well over a hundred thousand dollars — paid by you, to someone else, for a result that on average is no better.

That is not a reason to be paralysed by fees. It is a reason to check one number before you buy, and prefer the cheaper of two similar options.

Where to find it: the fund’s listing page on your brokerage shows it, and so does the prospectus. If you cannot find it easily, that is itself information.

One fee people miss: a percentage charged by an adviser sits on top of the fund’s own expense ratio. A 1% advisory fee plus a 0.60% fund is costing you 1.60% a year.

Target date funds, and why they hold bonds

A target date fund is a single fund that holds a mix of everything and adjusts that mix as you get older. You pick the one closest to the year you expect to retire and stop thinking about it.

When you look inside one, you will find it holds stocks and also bonds. A bond is a loan — you lend money to a government or a company, they pay you interest and return the principal at the end. Bonds usually move less than stocks, in both directions.

At your age the fund will hold mostly stocks, because you have decades to ride out declines. As the target year approaches it shifts gradually toward bonds, because someone about to retire cannot afford the kind of fall Section 42 documents.

That shift is the whole product. You are paying a small amount for someone to do the rebalancing you would otherwise have to remember to do.

Two things to check. The expense ratio, because target date funds vary widely and some are expensive. And the year, because people pick the one matching their graduation rather than their retirement, which is forty years off.

It is a genuinely good default. Choosing one and never touching it beats most of what people do instead.

Robo-advisers, honestly

A robo-adviser is a service that asks you some questions, builds a portfolio of index funds for you, and rebalances it automatically. Betterment and Wealthfront are the best known, and most large brokerages now offer one.

They typically charge around 0.25% a year on top of the underlying funds.

What they are genuinely good for: someone who will not otherwise start. If the alternative is money sitting in cash for two years because the fund list is intimidating, a robo-adviser is clearly better. Automatic rebalancing and tax-loss harvesting are real features.

The honest comparison: a single target date fund does most of the same job for less. You are paying the robo-adviser mainly for a nicer experience and the removal of one decision.

That can be worth 0.25%. Just know that is what you are buying, rather than believing it is a better portfolio.

And be clear about the difference between this and a human adviser charging 1% — see Section 44 on how to vet one of those.

Why you should not be checking it

Once the money is invested, the most useful thing you can do is very little.

Research on investor behaviour is consistent: the more frequently people look at their portfolio, the worse they do. Checking daily makes a normal decline feel like an emergency, and emergencies make people sell.

Comparing your return against an index, a friend, or a headline is the same trap in a different coat. Over forty years, the money you contributed and the fees you avoided will matter more than any performance difference you could chase.

A reasonable rhythm: look once or twice a year, confirm the contributions went in and got invested, confirm the expense ratio has not changed, and close the app.

If a target date fund is doing the allocating, there is nothing else to do. That is the point of it.

Where to check this yourself

investor.gov, run by the SEC, has plain-language explanations of every term here and a free compound interest calculator. Your brokerage's own listing page shows every fund's expense ratio and whether it tracks an index.