The sun is about halfway through it's main sequence, or "life". It is estimated that the sun is about four and a half billion years old.
Scientists predict that the sun will last about ten billion years as a "main sequence" star.
In another four and a half billion years, the sun will enter a Red Giant phase in it's life. During this phase, it will evelope the the three inner planets. So Earth will actually be swallowed by the elderly sun.
For thousands of years, as the sun expands ever close towards the Earth, the temperature will steadily increase. Global warming will take on a whole new meaning as the oceans begin to boil. This is the good news!
Every piece of flora and fauna will be completely obliterated before the sun actually swallows our rock into it's fiery depths.
