iShares is a family of exchange-traded funds (ETFs) managed by BlackRock. The first iShares ETFs were known as World Equity Benchmark Shares (WEBS) but have since been rebranded.Each iShares fund tracks a bond or stock market index. Stock exchanges listing iShares funds include the London Stock Exchange, American Stock Exchange, New York Stock Exchange, BATS Exchange, Hong Kong Stock Exchange, Toronto Stock Exchange, Australian Securities Exchange, and a number of European and Asian stock exchanges. iShares is the largest issuer of ETFs in the US and globally.