The exploration of properties of an extreme state of matter, the Quark--Gluon
Plasma, has broken new ground with the recent Run 2 operation of the Large
Hadron Collider with heavy-ion collisions at the highest energy to date. With
the heavy-ion data taken at the end of 2015, the ALICE Collaboration has made
the first observation of anisotropic flow of charged particles and related
phenomena in lead--lead collisions at the record breaking energy of 5.02 TeV
per nucleon pair. The Run 2 results come after the proton-lead collisions,
which provided a lot of unexpected results obtained with two- and
multi-particle correlation techniques. In these proceedings, a brief overview
of these results will be shown. We will discuss how they further enlighten the
properties of matter produced in ultrarelativistic nuclear collisions. We
indicate the possibility that, to leading order, the striking universality of
flow results obtained with correlation techniques in pp, p--A and A--A
collisions might have purely mathematical origin, and that physical conclusions
therefore could be drawn only from the subleading orders.Comment: 4 pages, 2 figures. Proceedings for Rencontres de Moriond conference,
March 19-26, 201