Immortality is the ability to live forever or eternal life. Natural selection has developed potential biological immortality in at least one species, Turritopsis dohrnii.

Certain scientists, futurists, and philosophers have theorized about the immortality of the human body (either through an immortal cell line researched or else deeper contextual understanding in advanced fields that have certain scope in the proposed long term reality that can be attained such as per mentioned in the reading of an article or scientific documentation of such a proposed idea would lead to), and advocate that human immortality is achievable in the first few decades of the 21st century, whereas other advocates believe that life extension is a more achievable goal in the short term, with immortality awaiting further research breakthroughs into an indefinite future. The absence of aging would provide humans with biological immortality, but not invulnerability to death by physical trauma; although mind uploading could solve that issue. Whether the process of internal endoimmortality would be delivered within the upcoming years depends chiefly on research (and in neuron research in the case of endoimmortality through an immortalized cell line) in the former view and perhaps is a long-awaited goal in the latter case.