There are several types of financial crises, including:

1. Banking crisis: A situation where there is a lack of liquidity or solvency within the banking system.

2. Currency crisis: A situation where the value of a currency drops rapidly, causing inflation and economic instability.

3. Debt crisis: A situation where a government or organization is unable to repay its debts.

4. Sovereign debt crisis: A situation where a government is unable to service its debt obligations.

5. Systemic crisis: A situation where there is a widespread failure of financial institutions or markets.

To prevent or mitigate financial crises, some measures that can be taken include:

1. Regulatory oversight: Governments should establish strong regulatory frameworks for financial markets and institutions, to prevent excessive risk-taking and ensure transparency.

2. Preparing for downturns: Governments and financial institutions should prepare for economic downturns by building up reserves, diversifying portfolios, and stress-testing their balance sheets.

3. Maintaining economic stability: Governments should implement policies that support economic stability and growth, such as maintaining low inflation and investing in infrastructure.

4. Improved corporate governance: Companies should improve their governance practices to avoid excessive risk-taking, ensure accountability, and improve transparency.

5. International cooperation: The international community should work together to coordinate policies and prevent financial contagion.