Immortality

When there pass before our eyes examples such as these, so frequent and so ordinary, how can we ever rid ourselves of thoughts of death or stop imagining that death has us by the scruff of the neck at every moment? Immortality is eternal life. An immortal being is supposedly immune to death. Many religions and cranks have promised eternal life, but none have been proven to deliver on the claim.

Biological immortality
Despite claims to the contrary, only a certain type of jellyfish may have any sort of claim to immortality (assuming they aren't eaten by predators).

Several plants also seem to have no age limit with some of the oldest examples found, such as the "Pando" clonal colony of quaking aspen in Utah, reaching tens of thousands of years old.

Genetic immortality
This view is that you can achieve a form of immortality through your genes being passed on to your children and through them, others. The downsides are how you will likely be forgotten after four or five generations and your descendants will quickly be as similar to you as you are to anybody else.

Supernatural immortality
Magic will grant you immortal life in Heaven! Or as a vampire. The first emperor of China's Qin dynasty died taking mercury pills in search of immortality.

Virtual immortality
Ha, we don't need that supernatural rubbish! We have cryonics and whole-brain emulation! Or we will have them, eventually. Or at least they don't provably contradict physics. YOU CAN'T PROVE THEY DO.

Cultural immortality
Make people remember your name (if not you) forever for longer than otherwise through good or bad deeds such as exemplary military service, political works, terrorist acts, artistic triumphs, etc. This can quickly fall into "The person they are remembering is barely a shadow of what they were". Woody Allen had this to say: "I don't want to achieve immortality through my work… I want to achieve it through not dying."

Desirability of immortality
Some traditions (such as Christianity) regard immortality favorably as a worthwhile goal. Greek mythology, on the other hand, which featured a separate privileged class of immortals (gods and demi-gods), warned against the hubris of average humans aspiring to better their status in stories such as that of Prometheus, and portrayed the disadvantages of eternal punishment, as in the tale of Tantalus.