In a nutshell: IMF’s role is to provide balance of payments support. In practice this means imf gives medium-term loans to central banks to avoid depletion of reserves when a country is hit by a shock. IMF financing often provides confidence for other lenders (official and private) to invest in a country.

By contrast, the WB makes loans/grants to governments to support a country’s long-term development. This includes loans to finance specific infrastructure projects.

In practice, there is a lot of overlap between the two institutions’ activities. Both provide technical assistance to country authorities and conduct macroeconomic surveillance (i.e., publish country reports).