Financial settlement periods used to be much longer: Before the early 1990s at the London Stock Exchange, for example, stock could be paid for up to 10 working days after it was bought, allowing traders to buy (or sell) shares at the beginning of a settlement period only to sell (or buy) them before the end of the period hoping for a rise in price. This activity was identical to modern day trading, but for the longer duration of the settlement period. But today, to reduce market risk, the settlement period is typically two working days. Reducing the settlement period reduces the likelihood of default, but was impossible before the advent of electronic ownership transfer.
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Range trading, or range-bound trading, is a trading style in which stocks are watched that have either been rising off a support price or falling off a resistance price. That is, every time the stock hits a high, it falls back to the low, and vice versa. Such a stock is said to be "trading in a range", which is the opposite of trending.[13] The range trader therefore buys the stock at or near the low price, and sells (and possibly short sells) at the high. A related approach to range trading is looking for moves outside of an established range, called a breakout (price moves up) or a breakdown (price moves down), and assume that once the range has been broken prices will continue in that direction for some time.

When it comes to intraday trading, daily charts are the most commonly used charts that represent the price movements on a one-day interval. These charts are a popular intraday trading technique and help illustrate the movement of the prices between the opening bell and closing of the daily trading session. There are several methods in which intraday charts can be used. Know about some of the most commonly used chart.
There is no special qualification required to become a day trader. Instead day traders are classified based on the frequency of their trading. FINRA and NYSE classify day traders based on whether he or she trades four or more times during a five-day span, provided the number of day trades is more than 6% of the customer's total trading activity during that period or the brokerage/investment firm where he or she has opened an account considers him a day trader. Day traders are subject to capital and margin maintenance requirements.
This trading strategy used to be defined as spread trading where you would take profits where small gaps expanded and contracted between the bid and the ask price for a stock. This strategy has now evolved to include technical indicators, support/resistance levels, and volume spikes to make round-trip trades lasting seconds to a few minutes. The basic idea of scalping is to take advantage of market inefficiencies using speed and high trading volume to create quick profits. Click here for more information on scalping.
Market data is necessary for day traders to be competitive. A real-time data feed requires paying fees to the respective stock exchanges, usually combined with the broker's charges; these fees are usually very low compared to the other costs of trading. The fees may be waived for promotional purposes or for customers meeting a minimum monthly volume of trades. Even a moderately active day trader can expect to meet these requirements, making the basic data feed essentially "free". In addition to the raw market data, some traders purchase more advanced data feeds that include historical data and features such as scanning large numbers of stocks in the live market for unusual activity. Complicated analysis and charting software are other popular additions. These types of systems can cost from tens to hundreds of dollars per month to access.[19]

You're probably looking for deals and low prices, but stay away from penny stocks. These stocks are often illiquid, and chances of hitting a jackpot are often bleak. Many stocks trading under $5 a share become de-listed from major stock exchanges and are only tradable over-the-counter (OTC). Unless you see a real opportunity and have done your research, stay clear of these.