  We review a recent global analysis of inclusive single-charged-hadron
production in high-energy colliding-beam experiments, which is performed at
next-to-leading order (NLO) in the parton model of quantum chromodynamics
endowed with nonperturbative fragmentation functions (FFs). Comparisons of p
p-bar data from CERN S p p-bar S and the Fermilab Tevatron and gamma p data
from DESY HERA with the corresponding NLO predictions allow for quantitative
tests of the scaling violations in the FFs and their universality. We emphasize
the potential of new measurements at the Tevatron to place tight constraints in
the large-x region and on the gluon FF, complementary to those from e^+ e^-
data, which are indispensible in order to reliably predict the pi^0 background
for the H -> gamma gamma signal of the intermediate-mass Higgs boson at the
Tevatron and the CERN LHC. Adopting a similar theoretical framework for
b-hadron production, we show that the notorious excess of the Tevatron data
over existing theoretical calculations can be ascribed, at sufficiently large
values of p_T, to nonperturbative fragmentation effects inadequately included
previously.
