A stock portfolio refers to a collection of stocks from various industries owned by an individual or institutional investor. Stocks within a portfolio are often evaluated as a whole, as the combined performance of different investments can counterbalance the ups and downs of individual stocks. Constructing a diversified stock portfolio is widely recognized as a way to mitigate risk in investing. 

For example, an investor’s stock portfolio might include shares from technology companies, retail businesses, manufacturing firms, and healthcare providers. This diversification ensures that if one particular sector performs poorly, the other sectors might still perform well and thus limit the overall loss. 

When creating a stock portfolio, investors usually consider their risk tolerance, investment objectives, and time horizon. The composition of a stock portfolio can typically be adjusted or rebalanced as needed, particularly when an investor’s financial situation or goals change. It’s important to continuously monitor and evaluate your portfolio’s performance against your investment goals and adjust it accordingly. This strategically diversified collection of securities aims to maximize returns and manage risk effectively.