Bonds are debt instruments issued by either large corporations or national governments to raise money. They are also popular among traders and investors, in particular because they offer diversification away from stocks. In addition, bonds are seen as less volatile assets that tend to be inversely correlated to stocks.
As a result of their popularity, bonds - and in particular government bonds from developed countries - are often offered by UK-registered forex & CFD brokers that are regulated by the Financial Conduct Authority (FCA). In general, these assets are seen as some of the safest investments in the world, and they are therefore particularly popular during times of financial turmoil.