How the Stock Market Actually Works
The conventions nobody explains: why prices are quoted in percentages, what a ticker symbol is, when the market is shut, and what the indicators on every chart are really measuring.
8 articles · about 42 min in total
Start with Why Stocks Have Ticker Symbols (and Why Apple Is AAPL, Not APPL)Every field has conventions that are obvious to insiders and invisible to everyone else. Finance has more than most, and a lot of them are historical accidents that nobody ever went back and explained.
Why a ticker is three letters, why a move is quoted as a percentage rather than in dollars, why a company would split a stock when it changes nothing about what you own. None of these are hard. They are just never covered, because the people writing about markets learned them so long ago they forgot they had to.
The second half of the path is the indicators. They are worth understanding for a specific reason: widely used things move prices whether or not they predict anything. Bollinger Bands are a moving average plus and minus a multiple of standard deviation. MACD is two moving averages subtracted. Knowing that removes the mystique and leaves the actual use.
The last step is the modern version of the same idea. Retail sentiment is now measurable in message volume, which is a genuinely new data source and a genuinely noisy one.
Key takeaways
- A stock split changes the share count and the price per share without changing the value of what you own or the company market capitalization.
- Price moves are quoted in percentages because a dollar move means something different on a $10 stock than on a $1,000 one.
- Bollinger Bands are a moving average plus and minus a multiple of standard deviation, so they describe recent volatility rather than predicting direction.
- MACD is the difference between two moving averages, which makes it a measure of momentum change rather than an independent signal.
Step 1: Why Stocks Have Ticker Symbols (and Why Apple Is AAPL, Not APPL)
Ticker symbols look like they should be obvious abbreviations. They aren’t. They’re a 19th-century engineering compromise that survived the move to electronic markets, and they still carry the fingerprints of how the system worked in 1867.
May 20, 2025 · 5 min read
Step 2: Why Stock Traders Quote Percentages, Not Dollars
A $1 move in a $5 stock and a $1 move in a $500 stock are not the same thing. Here's why traders almost never talk in dollars, and the few cases where they actually do.
Jan 28, 2025 · 5 min read
Step 3: What Is a Stock Split and Why Companies Still Do It
A stock split changes the number of shares and the price per share while leaving the total value of your position untouched. So why do companies bother? The honest answer is signaling, accessibility, and a little bit of psychology.
May 24, 2026 · 8 min read
Step 4: When Is the Stock Market Actually Closed
The NYSE closes for ten full holidays a year, plus three early-close days, plus the occasional emergency. Here’s the full calendar and the surprising history behind some of the dates.
Feb 11, 2025 · 4 min read
Step 5: The Top 10 Stock Indicators, Explained Without the Mysticism
Most charting platforms let you stack 100+ indicators. Ten of them do almost all the useful work. Here’s what each one actually measures, and why you can ignore the rest.
Apr 8, 2025 · 4 min read
Step 6: What Is MACD: The Indicator Behind Half the Charts You See
MACD is the most-quoted technical indicator on the internet. It’s also one of the simplest. Two moving averages, a difference, and a signal line. Here’s how it actually works, and where it fails.
Mar 25, 2025 · 5 min read
Step 7: Bollinger Bands: The Indicator That’s Mostly Standard Deviation
Bollinger Bands are a 20-day moving average with two lines drawn two standard deviations away. The math is high school stats. The hard part is knowing what to do with them.
Apr 1, 2025 · 6 min read
Step 8: StockTwits, Sentiment, and Message Volume: What the Numbers Actually Mean
StockTwits is one of those products that’s either useless or genuinely informative depending on how you read it. The sentiment score and message volume are simple metrics, but their value comes from context.
Apr 29, 2025 · 5 min read
Frequently asked questions
- What does a stock split actually do?
- It increases the share count and reduces the price per share proportionally, so the value of your holding and the company market capitalization are unchanged. Companies do it mainly to keep the nominal share price in a range that feels accessible to retail buyers.
- Why are stock moves quoted in percentages instead of dollars?
- Because a dollar is not comparable across prices. A $1 move on a $10 stock is a 10% event and the same move on a $1,000 stock is a rounding error. Percentages make moves comparable between companies and across time.
- What is MACD measuring?
- The difference between a shorter and a longer moving average of price, plus a signal line that smooths that difference. It is a momentum indicator, so it describes whether recent price movement is accelerating relative to the longer trend.
- Do technical indicators actually work?
- They describe what price has already done rather than what it will do. That still matters, because enough participants watch the same levels to make them briefly self-fulfilling. Treat them as a description of crowd behavior, not as a forecast.