Firms that use high-speed computers and communications networks to execute millisecond trades for themselves
Explanation:
High Frequency traders are different entities that take part in the market that use powerful computers to be able to be fast at answering to news and have a big number of trades. These traders use advance tools to evaluate the markets and anticipate trends quickly to obtain profits from the trades they make. According to this, the answer is that High Frequency Traders are Firms that use high-speed computers and communications networks to execute millisecond trades for themselves.
