SIPP stands for Self-Invested Personal Pension. It is a type of pension scheme available in the United Kingdom. With a SIPP, individuals have more control over their pension investments compared to traditional pension funds. They can choose from a wide range of investment options, including stocks, bonds, and property. SIPP offers flexibility in terms of contributions and allows individuals to take tax-free cash lump sums from the age of 55. It is a popular choice for individuals who want to have more control and flexibility over their retirement savings.