UK100 is the ticker symbol used to represent the FTSE 100 index, which is a stock market index composed of the 100 largest companies listed on the London Stock Exchange (LSE) by market capitalization. It is a widely used benchmark for measuring the performance of the UK stock market and economy as a whole. The companies included in the index cover a wide range of sectors, including banking, mining, oil and gas, and retail. The UK100 is one of the most widely traded indices in the world and is closely followed by investors and traders globally.