[chollida1]

Algorithmic trading and high frequency trading are orthogonal concepts.

High frequency trading typically refers to two concepts. 1) how long you hold your position, 2) how quickly you can send/cancel existing orders. Though I'll hedge and say there isn't a really accepted definition of high frequency.

Algo trading on the other hand refers to using a computer to automate trading strategies. The typical example is a pair trade with Ford and GM. When they deviate you sell one and buy the other, when the prices come back together you reverse the trade and sell the first leg and buy the second.

Algo trading is here to stay. High frequency has typically been more arbitrage focused and its followed the pattern that happens to all arbitrage opportunities and gone away as more people got in on the action.