FTSE stands for the Financial Times Stock Exchange. The FTSE indexes are owned by FTSE Russell, part of the London Stock Exchange Group. The best known indexes are the FTSE 100, made up of the largest 100 companies trading on the London Stock Exchange, and the FTSE 250, made up of the next largest 250 companies on the exchange.
FTSE Group was created by Pearson, then owner of the Financial Times newspaper and the London Stock Exchange, in 1995. Pearson sold its stake to the LSE in 2011. The LSE went on to acquire index provider Frank Russell in 2014, combining it with FTSE Group to form FTSE Russell.
There are several FTSE indexes, including those based on market capitalisation like the FTSE 100, FTSE All-Share, FTSE MIB and FTSEurofirst, fixed-income indexes including the FTSE MTS and FTSE TMX, and sustainable investment index FTSE4Good.