What's the difference between investing and joining?

Investment means that one or more people put money or technology into a certain industry, which is often risky but has good returns, and is suitable for people with abundant funds and certain skills. (investment is often on an equal footing with others or has a higher status than others. Joining refers to cooperating with others, often with less investment and low technical requirements, and is suitable for people with insufficient funds and stable income, but the income is not as good as that of investment. (Joining is often because you are young and others are old. )