The Stock Exchange does not deal in treasury bills.
Treasury bills are short-term debt securities issued by governments to raise funds from the public. They are usually issued for a period of less than one year and are considered to be very safe investments as they are backed by the government. However, they are not traded on the stock exchange.
On the other hand, shares, debentures, stocks, and bonds are all securities that are traded on the stock exchange. A share represents ownership in a company, while a debenture represents a loan that a company has taken out. Stocks and bonds are similar to shares and debentures, respectively, but they may be issued by governments or other organizations.
In summary, the stock exchange deals in various securities, including shares, debentures, stocks, and bonds, but not treasury bills.