Major tech firms have seen their stock values fall after a sell-off by investors following the US midterm elections.
The fall in the value of their shares across the world has been blamed on an expectation of a slowdown in AI development, although it comes after sharp rises over recent years.
As companies grow, they may issue shares. Many of the largest companies in the UK have shares which are bought and sold on the London Stock Exchange.
Their collective performance is often quoted amid a blizzard of numbers that may feel confusing and irrelevant.
Booms or falls in the stock market make the news, but rarely does anyone mention the FTSE 100 during a coffee with friends.