The stock market is closed at noon from 11:30 to 13:00. The opening and closing times of the Shanghai and Shenzhen stock markets are the same: they officially open at 9:30 a.m. and close at 11:30 a.m., with a one-and-a-half-hour lunch break. They open at 13:00 p.m. and close at 15:00 p.m. The collective bidding time of Shanghai and Shenzhen markets is from 9:15 to 9:25 every day, and the collective bidding time of Shenzhen and Shenzhen markets is from 14:57 to 15:00 in the afternoon. There will be no trading on Saturdays, Sundays and closing days announced by the Shanghai Stock Exchange. Stock market is the abbreviation of stock market. The stock market is equivalent to a platform or place that can provide various stock trading services. Stock trading services may include: stock listing and issuance, stock buying and selling, stock transfer and circulation, etc. The stock market can be divided into primary market, secondary market, tertiary market and quaternary market. Among them, the primary market is the issuance market; the secondary market, the tertiary market and the fourth-level market are the circulation markets. At present, my country has three major stock trading markets: Shanghai Stock Exchange, Shenzhen Stock Exchange and Hong Kong Stock Exchange. The primary market is the market where stocks are listed and new shares are issued. The stocks that appear in the primary market are generally the stocks issued for the first time by a listed company or the stocks issued by a listed company on the basis of the original stocks. They are also vividly called "one-lot stocks" by investors. The secondary market is the market where stock transactions occur between investors who purchase "one-lot shares" and other stock investors. "One-lot shares" become "second-hand shares" or "multi-lot shares" after being traded, changed hands, and circulated. The secondary market can not only provide a platform for the circulation of stocks, but also generate cash value for transactions between investors. The secondary market can be divided into stock exchanges and over-the-counter markets. The secondary market is the largest and most important market in the stock market, and its power and influence are also the greatest. The tertiary market is a stock market that combines the functions of a stock exchange and an over-the-counter market. The third-level market transforms stocks that could only be traded on stock exchanges or over-the-counter into stocks that can be traded on both the securities exchange market and the over-the-counter market. The fourth-level market is a market where large institutions or extremely well-capitalized individuals use computer communication networks to directly conduct bulk transactions such as stocks, securities, futures, options, etc. in order to save time and save commissions and other expenses.