Which of the following organization/s make/s up the World Bank?

General perception is the World Bank means IBRD only, but official website says its IBRD and IDA both. Founded in 1944, the International Bank for Reconstruction and Development—soon called the World Bank—has expanded to a closely associated group of five development institutions. Originally, its loans helped rebuild countries devastated by World War II.  In time, the focus shifted from reconstruction to development, with a heavy emphasis on infrastructure such as dams, electrical grids, irrigation systems, and roads.  With the founding of the International Finance Corporation in 1956, the institution became able to lend to private companies and financial institutions in developing countries.  And the founding of the International Development Association in 1960 put greater emphasis on the poorest countries, part of a steady shift toward the eradication of poverty becoming the Bank Group’s primary goal. The subsequent launch of the International Centre for Settlement of Investment Disputes and the Multilateral Investment Guarantee Agency further rounded out the Bank Group’s ability to connect global financial resources to the needs of developing countries.