  Since 2014, MUSE, the Multi-Unit Spectroscopic Explorer, is in operation at
the ESO-VLT. It combines a superb spatial sampling with a large wavelength
coverage. By design, MUSE is an integral-field instrument, but its
field-of-view and large multiplex make it a powerful tool for multi-object
spectroscopy too. Every data-cube consists of 90,000 image-sliced spectra and
3700 monochromatic images. In autumn 2014, the observing programs with MUSE
have commenced, with targets ranging from distant galaxies in the Hubble Deep
Field to local stellar populations, star formation regions and globular
clusters. This paper provides a brief summary of the key features of the MUSE
instrument and its complex data reduction software. Some selected examples are
given, how multi-object spectroscopy for hundreds of continuum and
emission-line objects can be obtained in wide, deep and crowded fields with
MUSE, without the classical need for any target pre-selection.

Instrumentation and Methods for Astrophysics