Hydrogen energy is a kind of secondary energy, unlike coal, oil and natural gas, which can be directly exploited, but it is made from other energy sources in a certain way.

1.ETF is a transactional open index fund, commonly known as exchange traded fund (ETF). It is an open-end fund listed and traded on the exchange, and the fund share is variable. According to different investment methods, ETFs can be divided into index funds and actively managed funds.

2.ETF index fund, ETF index fund represents the ownership of a basket of stocks. Refers to index funds that are traded on the stock exchange like stocks. It takes a specific index as the target index. The transaction price and net value trend of fund shares are basically consistent with the tracking index. At present, the mainstream target indexes in the market are Shanghai and Shenzhen 300 Index and S&P; Investors such as P 500 Index, Nasdaq 100 Index buy and sell an ETF index fund, which is equivalent to buying and selling the index it tracks, and can get basically the same income as the index. Usually a completely passive management mode is adopted to fit an index, which has the characteristics of stocks and index funds.

3. Representative ETF index funds: SSE 50ETF, SSE 50ETF is one of the most representative blue-chip indexes in Shanghai. This is an innovation fund. At the same time, SSE 50 Index is the tracking target of the first traded open index fund (ETF) in China. Shanghai-Shenzhen 300ETF and Shanghai-Shenzhen 300ETF are transactional open index funds with the Shanghai-Shenzhen 300 index as the target and trading, subscription and redemption in the secondary market. It is a heavyweight ETF fund in China market. When there is a difference between the transaction price of ETF secondary market and the net value of fund shares, investors can carry out arbitrage trading.

4. Small and medium-sized board ETF, that is, small and medium-sized board index fund, is a representative stock selected from A shares listed and traded in small and medium-sized board of Shenzhen Stock Exchange. Small and medium-sized board index is a comprehensive index based on all listed stocks of small and medium-sized board in Shenzhen Stock Exchange. Sampling index is the ratio of the average market value of circulation to the average transaction amount in a period of time (usually in the first six months).

5. GEM ETF, GEM ETF is an index fund that constructs a stock portfolio according to the composition and weight of GEM index stocks. GEM index selects 100 sample stocks from GEM stocks, reflecting the operation level of GEM market. It is one of the core indicators reflecting the operation of listed stocks in Shenzhen Stock Exchange.