A capital asset is something that offers an ongoing stream of value, and can be valued by a net present value calculation that discounts the stream of value. An example would be equities that provide a stream of dividends, or bonds that pay interest. In both cases, one expects the principal amount back in time. The value of both these instruments will increase or decrease as the investor decreases or increases the discount rate used to value the asset. 
A company can issue both equity and bonds, the difference in the characteristics of these instruments being because of the capital structure, with bonds ranking ahead of equities, but with limited participation in the economic benefits the company generates. Ultimately, the basic method of valuing the asset will remain the same. 

• Traditional View on Asset Classes
• Capital Assets
• Consumable or Transformable
• Store of Value Assets
• Human Capital
• Reference or Additional Material