The World Bank Group is five institutions: IBRD, IDA, IFC, MIGA and ICSID
Background
The World Bank Group has five organizations: the International Bank for Reconstruction and Development (IBRD), the International Development Association (IDA), the International Finance Corporation (IFC), the Multilateral Investment Guarantee Agency (MIGA) and the International Centre for Settlement of Investment Disputes (ICSID).
IBRD, created in 1944 to help Europe rebuild after World War II, provides loans, guarantees and advisory services to middle-income and creditworthy low-income countries.
IDA offers grants and low-interest loans to low-income countries; IBRD and IDA together form the World Bank.
IFC encourages the growth of the private sector in developing countries.
MIGA provides political risk insurance (guarantees) for projects in developing member countries, while ICSID is, in the World Bank's own description, the world's leading institution devoted to international investment dispute settlement.
In plain words
IBRD International Bank for Reconstruction and Development — The World Bank Group's lender to middle-income and creditworthy low-income countries.
IDA International Development Association — Gives grants and low-interest loans to low-income countries.
IFC International Finance Corporation — Promotes private-sector growth in developing countries.
MIGA Multilateral Investment Guarantee Agency — Insures projects in developing member countries against political risk.
ICSID International Centre for Settlement of Investment Disputes — The World Bank Group institution devoted to international investment dispute settlement.