  We briefly outline recent observations by solar spacecraft such as Yohkoh,
SOHO, TRACE, and RHESSI, which have revolutionized what we know and don't know
about the Sun. We then present some significant results, mainly from SUMER/SOHO
but also complimentary from the other SOHO's experiments, such as CDS, EIT,
UVCS, and LASCO. In particular, we present density-temperature structures,
explosive events, velocity anisotropy, wave activity, coronal holes and the
solar wind etc. These results have provided valuable clues to a better
understanding of the two of the SOHO's principal scientific objectives namely,
how the Sun's magnetic energy heats its million-degree corona, and feeds the
solar wind.
