Venture capital is the money a private group invests in a new, exciting business. Well-known startups like Spotify and WhatsApp owe much of their success to venture capital.
In the business world, the term venture capital is a common way to talk about a fairly risky type of investment. When a brand new or growing business needs a large amount of money (or capital), its owners often seek venture capital, offering partial ownership in return. The banks, groups, or individuals who invest venture capital are taking a chance (that's the venture part of the equation), hoping that their investment will pay off eventually.