MCMC algorithm -- understanding some paremeters

I am trying to understand an MCMC program. I manage to run it, but I am trying to understand the meaning of the some parameters in the analysis.

The code is something like this

#Nsamples
nsamp   = 50000

#Burn-in
skip    = 300

#temperature at which to sample
temp    = 2

#Gelman-Rubin for convergence
GRstop  = 0.01

#every number of steps check the GR-criteria
checkGR = 500

#1 if single cpu , otherwise is giving by the nproc- mpi -np #
chainno = 0

This is for the metropolis-hastings algorithm.

How my results depend on these parameters or what these parameters mean ?

I understood the nsamp and skip, I also kind of know what GRstop and checkGR means but I have no idea what temp and chainno means. How does changing these parameters can effect the analysis ?