Many novice investors have this kind of confusion: why does buying and selling stocks in the Taiwan stock market feel very expensive, while in the U.S. stock market it's much cheaper? The simple reason behind this is that different stock markets have different trading unit sizes. Today, let's talk about the basic concept of one lot of shares and the trading rules in different stock markets.

First, you need to understand what the stock price is. The stock price is the trading price of a stock, used to indicate how much money an investor needs to spend to buy one share of stock. In the stock market, stock prices usually fluctuate in real-time per share, changing according to the latest transaction prices between buyers and sellers. Different countries' stocks are priced in different currencies, such as U.S. stocks in USD, Taiwan stocks in TWD, and Hong Kong stocks in HKD.

Next, you need to understand what one share is. Listed companies are all joint-stock companies, and one share is the smallest trading unit. For example, in Taiwan, most companies' stock par value is 10 TWD, because Taiwan used to implement a fixed par value system. But note that the par value of a stock has little to do with its market price; the par value just records the original capital contribution, while the actual stock price is determined by the company's profitability and investor expectations. Therefore, for investors, the price of one share is simply the current market price.

For example, in August 2023, the price of one Tesla share in the U.S. stock market was $254.11. In January of the same year, Tesla was only $101.81 per share, so in just seven months, the stock price more than doubled. The same logic applies to the Taiwan stock market: in April 2024, the price of one Taiwan Cement share was 32.10 TWD, and investors look at this real-time market price.

Now, let's talk about the issue of how many shares are in one lot. The trading unit size varies across different stock markets. The trading unit in the U.S. is 1 share, in Hong Kong it's 1 lot, and in Taiwan it's 1 lot. The key point is that in Taiwan, 1 lot equals 1,000 shares.

In other words, buying one lot of stock in Taiwan is equivalent to buying 1,000 shares. For example, if TSMC's current price is 1080 TWD per share, then to buy one lot of TSMC, you need to spend 1080 multiplied by 1000, which equals 1,080,000 TWD. In contrast, buying the same number of Tesla shares in the U.S., if the current price is $420 per share, only costs $420.

Hong Kong's situation is a bit more complicated. The number of shares in one lot depends on the stock price; one lot could be 100, 500, 1000, or 2000 shares. For example, Tencent's current price is 418 HKD per share, and one lot of Tencent contains 100 shares. So, trading one lot of Tencent requires 418 HKD multiplied by 100, which equals 41,800 HKD.

To summarize, U.S. stocks have the lowest investment threshold and the most flexible trading. Investing in Taiwan and Hong Kong stocks requires more initial capital. For investors with limited funds, you can start by understanding these basic trading rules and then choose the appropriate investment method based on your situation.