In order to properly conduct fundamental and technical analysis on publicly-traded, companies, many traders turn to stock market software. Traditionally, this software is downloaded from the software creator and installed on your personal computer. The software runs on your computer and connects to the Internet to gather the most recent stock data.
Stock data (both fundamental and technical) is usually delayed 15-20 minutes, but can be real-time if either 1) a trader pays an extra monthly fee or 2) it is included from the software provider.
If you have a full-time day job and don't watch the live markets for entry and exit points, then you may want to save money and not pay for real-time data. Swing traders and position traders likely do not need real-time data for their stock market software.
Many modern traders prefer online trading software instead of downloadable software. The primary benefit is the ability to analyze publicly-traded companies from any Internet-connected computer in the world. All of a trader's portfolios, chart settings and saved data is stored on a software server instead of the trader's personal computer.
Online trading software has greatly evolved over the last decade. Years ago, it was much less powerful than its downloadable counterparts were. Today, online software is robust and has just as many features and capabilities as a downloadable version.