An ETF is an exchange-traded fund, a type of fund that is listed on an exchange and has a variable portion of the fund. Generally, an ETF is an index fund that invests passively by tracking all or part of the securities that make up an index according to the types and proportions of the securities that make up the index. Its trading hours are more flexible than those of other funds, so it can be traded during business hours just like stocks.
An ETF is an index fund that tracks an index or an industry.
An example: The S&P 500ETF (SPY)
The S&P 500 ETF is a fund that tracks the S&P 500 Index of the United States. In other words: When the S&P 500 goes up, it goes up; when the S&P 500 goes down, it goes down with it.
You can search for “ETF” in the Tiger Trade app. There are many related funds.