A life insurance policy is referred to as whole life because the insured is meant to have the policy for the entire span of their life. A twenty five year old person could conceivably have life insurance coverage up to retirement at the age of sixty five should they so choose by purchasing a whole life insurance policy. The reason why a young person may decide to have a whole life policy for that length of time is because, unlike term life insurance, whole life has what is called a cash component meaning the premiums paid into the policy build up the cash value for the life of the policy.
The investment aspect of a whole life policy can lead to a significant amount of cash value over the many decades that an individual is paying premiums. The cash value which builds is not taxed until it was withdrawn for use. The cash value can also be borrowed against as a loan and used for various expenses by the policyholder.
Whether or not the cash value investment aspect or loan aspect of a whole life insurance policy is important depends on spending habits, investment goals, and lifestyle decisions. For certain individuals, it may be more prudent to purchase a term life insurance policy with lower premiums for a fixed amount of time and take the difference in savings between the two policies and invest in different types of stocks, bonds and mutual funds which may lead to higher returns and a more diversified portfolio.
Like other types of life insurance, the policyholder must qualify first often by having a physical exam, by providing a full medical history, and possibly requiring additional blood work. If a whole life insurance policy is purchased when young and healthy the premiums can be substantially lower than purchasing a similar policy later in life. However, whole life insurance premiums are more expensive than term life insurance because of the additional cash component and would need to be considered when deciding on purchasing a whole life insurance policy.
If you're a financially savvy individual who likes making your own investment decisions and is able to contribute to savings and investment accounts then it may be better to purchase a term life insurance policy and invest the difference. But if you like the cash value aspect of a whole life insurance policy it may be better to pay fixed premiums for the life of the policy while investing at the same time which could provide an additional cash cushion at retirement. When speaking with a life insurance professional ask a lot of questions, read all the documents and don't sign anything unless you're sure what you're purchasing is right for you.