Mid-cap stocks refer to shares of companies with a market capitalization typically between $2 billion and $10 billion. These companies are often in a growth phase, balancing the stability of larger firms with the potential for higher returns associated with smaller companies. Investors may find mid-cap stocks appealing for their ability to grow while still being relatively established in their industries. Investing in mid-cap stocks can offer diversification in a portfolio, as they may perform differently than both large-cap and small-cap stocks. They can be more volatile than large-cap stocks but generally less risky than small-cap stocks, making them a middle-ground option for investors looking for growth opportunities without excessive risk.