If you've spent more than five minutes on finance TikTok, you've seen the acronyms. VOO. FXAIX. ETF. S&P 500. People talk about them like everyone already knows what they mean — and if you don't, you feel like you missed a class nobody told you about.

You didn't miss anything. Nobody teaches this. Here's what you actually need to know.

Step 1 — What Even Is an ETF?

ETF stands for Exchange-Traded Fund. Think of it like a basket of stocks. Instead of picking one company to invest in (which is risky — that company could tank), you buy a basket of hundreds of companies at once.

An ETF trades on the stock market just like a single stock. So if you buy one share of VOO, you're actually getting a tiny slice of every company in the S&P 500 — Apple, Microsoft, Amazon, 497 more. One purchase, 500 companies.

smobyday tip

ETFs are how most everyday investors actually build wealth. Not by picking hot stocks. Not by timing the market. By buying boring baskets of companies and leaving them alone.

Step 2 — VOO vs FXAIX: What's the Difference?

Both track the S&P 500. That means both hold essentially the same 500 companies. The difference is who runs them:

VOO is Vanguard's S&P 500 ETF. Expense ratio: 0.03%. Works on any brokerage — Fidelity, Schwab, Robinhood, all of them. Ticker: VOO.

FXAIX is Fidelity's S&P 500 Index Fund (technically a mutual fund, not an ETF — but same idea). Expense ratio: 0.015%. Only available on Fidelity. No minimum investment. Ticker: FXAIX.

If you invest on Fidelity, FXAIX is slightly cheaper and has no minimums. If you're anywhere else, VOO works perfectly.

smobyday tip

Both funds have returned around 10% annually on average over the long term. Not every year — some years it drops. But over 10+ years, the historical trend is consistent growth. This is why people keep coming back to them.

Step 3 — How Do I Actually Buy One?

You need a brokerage account. If you don't have one yet, Fidelity or Schwab are my top picks — no fees, no account minimums. Once your account is funded:

Search the ticker (VOO or FXAIX). Click Buy. Enter the dollar amount or number of shares. Confirm.

That's it. You now own a piece of 500 American companies.

Step 4 — Use This Prompt to Research Any ETF

Before I buy any ETF, I paste this into Claude or ChatGPT and read what comes back. Copy it, customize the fund name, and get a real breakdown in plain English.

AI Prompt — ETF Research
I want to understand [ETF or fund name] before I invest in it. Can you explain: 1. What index or benchmark does it track? 2. What are the top 10 holdings and what % of the fund do they make up? 3. What is the expense ratio and why does it matter for long-term returns? 4. How has it performed over 1 year, 5 years, and 10 years? 5. What are the risks I should know about? 6. Is this a good fit for someone who wants long-term growth with low maintenance? Please explain everything in plain language — I'm new to investing.

The answer won't tell you what to do — and it shouldn't. But it'll give you actual information to make a real decision. That's all you need to get started.