An individual who engages in the transfer of financial assets in any financial market, either for themselves, or on behalf of a someone else. The main difference between a trader and an investor is the duration for which the person holds the asset. Investors tend to have a longer term time horizon, whereas traders tend to hold assets for shorter periods of time in order to capitalize on short-term trends.

One main problem with engaging in short-term trading is commission costs. Because traders frequently engage in short-term trading strategies to chase after profit; they often rack up large commission fees. However, an increasing number of highly competitive discount brokerages has made this cost less of an issue.