Trading when you have retired from your employment is vastly different than when you are younger and employed. The focus and objectives are different. When you still have many years of employment, you can afford to put aside funds to trade with, to see if you can get a better return than a registered retirement plan. Or just for fun, because trading is a lot of fun. It is also addictive and very risky.
When you are retired, your main focus is to at least preserve capital, and hopefully grow it more than the “safe” funds you might have them in.
What is trading or day-trading?
You can “buy and hold” stocks, which most people do in their portfolios. For the most part long-term winners make up for the losers. Or you can trade on a more regular basis – being in and out of a financial instrument within the same day or within 2-3 days. This is “day-trading”. Or you can trade much more rapidly, especially in currencies where you can trade several times within a day, or sometimes within an hour.
I believe most people in general day trade stocks, commodities, futures and funds because it can be very interesting, challenging and have at least a hope of some good returns. I know personally a currency trader who makes easy well into the double digits every year on his account. And it is accumulative. As the account grows, he ups the lot size on his trades. It is all about risk/reward ration and money management.