Some term insurance plans offer you the option of converting your temporary life insurance (term) into a permanent policy which will not expire.
Most term life insurance offer this as an option, but you need to advise the insurer of your intent to convert your coverage by a specific date (usually stated in the policy).
This is for people who may decide they need life insurance for the rest of their lives, after having purchased temporary (term) life insurance coverage.
Learn about convertible term life insurance and how it works.