  Strange metals develop near quantum critical points (QCPs) in a variety of
strongly correlated systems. Some of the important issues include how the
quantum critical state loses quasiparticles, how it drives superconductivity,
and to what extent the strange-metal physics in different classes of correlated
systems is interconnected. In this review, we confront some of these issues
from the vantage point of heavy fermion metals. We will describe the notion of
Kondo destruction and how it leads to a transformation of the Fermi surface
from ``large" to ``small" when the system is tuned across the QCP, a loss of
quasiparticles everywhere on the Fermi surface when it is perched at the QCP,
and a dynamical Planckian scaling in various physical properties including
charge responses. We close with a brief discussion about the connections
between the strange-metal physics in heavy fermion metals and its counterparts
in the cuprates and other correlated materials.
