dd637b1b_Particles_vs__strings__particles
[topic] confinement [strings] Strings can describe properties of hadrons of all mass, and agree with qualitative properties of hadron scattering. But known string theories don't fit well to experiment, since they include massless hadrons. [particles] 
Qualitative arguments predict confinement of quarks and gluons inside hadrons, but calculations are limited to low-energy properties of hadrons (or high-energy properties of quarks and gluons), and cannot calculate properties of any but the lightest hadrons.
Particles vs. strings
particles