A broker is an individual or firm that acts as an intermediary between an investor and a securities exchange. They are licensed professionals who have the authorization to buy and sell stocks or other financial instruments on behalf of their clients. Brokers earn their income through commissions or fees that are based on the size or value of the transaction they facilitate. 

For beginners, brokers offer valuable services like personalized advice and investment guidance, and they have access to the trading platforms where transactions happen. They execute the investor’s orders to buy or sell stocks, bonds, mutual funds, and other assets, and they can also manage portfolios. 

There are various types of brokers including full-service brokers who offer a wide range of services like investment and retirement advice, tax guidance, and regular portfolio updates. On the other hand, discount brokers, like Define Edge Securities and Zerodha carry out buy and sell orders at a reduced commission but they don’t provide investment advice. It’s important to understand that while brokers can help navigate the investing process, it is ultimately the investor’s responsibility to make informed decisions.