  These lectures about lattice field theory were written for, and given at,
TASI 2019, ``The many dimensions of quantum field theory.'' The students at
this TASI were mostly interested in formal things, and so these are slightly
unusual lattice lectures: I wanted to give the physical motivation behind
lattice calculations rather than describe all the technical details. A quick
outline: (1) The really big picture: lattice basics, lattice confinement,
getting rid of the lattice. (2) A walk through the parts of a lattice
calculation -- an overview, to show what's involved. (3) Chiral fermions on the
lattice. (This part might be interesting to lattice people.) (4) Case studies:
the three dimensional Ising model, and QCD.
