If you go Long and Short, then you are a trader. The only difference is the time frame. The same TA principles apply to a 1 min chart as a one day chart, so the characterization of "day traders" as gamblers as compared to longer time frames is a distinction without a difference, IMHO. "Investors" are typically longer time frames (weeks to months) and often are Long only, although they may exit the market periodically as profit and/or loss targets are hit.