Learn
Stocks, in plain English
New to investing? No problem. Everything below is written like a friend explaining it over coffee — no jargon, no pressure.
The fundamentals
What is a stock?
A stock is a tiny piece of ownership in a company. When you buy one share of Apple, you literally own a small slice of Apple Inc. If the company does well, your slice becomes more valuable.
Example: Apple has about 15 billion shares. If you own 1, you own 1/15,000,000,000th of Apple.
What is a watchlist?
A watchlist is just a list of stocks you're keeping an eye on. No money involved — you're not buying anything. You're just tracking how their prices move over time.
Think of it like: adding items to a wishlist on Amazon. You're watching, not buying.
What does green and red mean?
Green means the stock price went UP since the market opened this morning. Red means it went DOWN. The percentage tells you by how much.
Example: AAPL +2.3% means Apple's price rose 2.3% today. On a $200 stock, that's +$4.60.
When is the market open?
The US stock market is open Monday to Friday, 9:30am to 4:00pm Eastern Time. Outside those hours, prices don't change.
Note: Peek shows the last known price when the market is closed. That's completely normal.
Reading the numbers
Stock price
The price is what one share costs right now. A high price doesn't mean the stock is expensive or a good investment — it just means one share costs that much.
Example: Amazon at $185/share and a small company at $5/share. Price alone tells you nothing about quality.
Market cap
Market cap is the total value of the whole company. It's calculated by multiplying the share price by the total number of shares.
Formula: Share price × Total shares = Market cap
$185 × 10B shares = $1.85 Trillion
P/E ratio
P/E stands for Price-to-Earnings. It tells you how expensive a stock is compared to how much money the company actually makes. Lower usually means cheaper.
Example: A P/E of 15 means you pay $15 for every $1 of annual profit. A P/E of 50 means you're paying a premium.
Open & close price
The open price is what the stock cost when the market opened this morning. The previous close is what it cost at the end of yesterday.
Example: Prev. close $180, Open $182 — the stock gapped up $2 overnight.
Portfolio basics
What is a portfolio?
A portfolio is all your investments together. In Peek, your portfolio value adds up every stock you're tracking based on how many shares you've entered.
Example: 5 shares of AAPL at $185 + 2 shares of TSLA at $220 = $925 + $440 = $1,365 portfolio
Gain & loss
Your gain or loss is how much money you've made or lost today. Peek shows this in the summary — but only if you've entered how many shares you hold.
Example: You hold 10 shares of NVDA. NVDA is up $3.50 today. Your gain = 10 × $3.50 = +$35.00
Quick glossary
TICKER
The short code for a stock. Apple = AAPL, Tesla = TSLA, Netflix = NFLX.
SHARE
One unit of ownership in a company.
BULL MARKET
When the market is going up over time. Everyone's optimistic.
BEAR MARKET
When the market is going down over time. Prices drop 20%+ from recent highs.
DIVIDEND
Money a company pays you just for owning its stock. Not all companies do this.
VOLATILITY
How much a stock's price swings up and down. High volatility = bigger moves.
INDEX
A group of stocks tracked together. The S&P 500 tracks the 500 biggest US companies.
NASDAQ
A US stock exchange. Most big tech companies (Apple, Google, Meta) trade here.
NYSE
New York Stock Exchange. The largest stock exchange in the world by value.
One last thing
Don't judge a stock by one day.
Stocks go up and down every single day — that's completely normal. What matters is the long-term trend. A stock being red today doesn't mean it's a bad company. Focus on learning how to read the numbers before making any real investment decisions.