There are two major types of day traders: institutional and retail.
An institutional day trader is a trader who works for a financial institution. This type of trader has certain advantages over retail traders as he/she generally has access to more resources, tools, equipment, large amounts of capital and leverage, large availability of fresh fund inflows to trade continuously on the markets, dedicated and direct lines to data centers and exchanges, expensive and high-end trading and analytical software, support teams to help, and more. All these advantages give them certain edges over retail day traders.
A retail day trader is a trader who works for himself, or in partnership with a few other traders. A retail trader generally trades with his own capital, though he may also trade with other people's money. Law has restricted the amount of other people's money a retail trader can manage. In the United States, day traders may not advertise as advisors or financial managers. Although not required, nearly all retail day traders use direct access brokers as they offer the fastest order entry and to the exchanges, as well as superior software trading platforms.
In the past, most day traders were institutional traders due to the huge advantages they had over retail traders. However, since the technology boom in the second half of the 1990s, advances in personal computing and communications technology, realized in the accessibility of powerful personal computers and the Internet, have brought fast online trading and powerful market analytical tools to the mainstream. Low, affordable commissions from discount brokers as well as regulation improvements in favor of retail traders have also helped level the trading playing field, making success as a retail trader a possibility for many and a reality for some.
An auto trader is the person who performs auto-trading, which stands for automated trading and the use of computer programs and other tools to enter trading orders. Because this all happens with the help of the computer algorithm it is also called algorithmic trading.