JAGS is Just Another Gibbs Sampler. It is a program for the analysis
of Bayesian models using Markov Chain Monte Carlo (MCMC) which is not
wholly unlike OpenBUGS (http://www.openbugs.info). JAGS was written
with three aims in mind: to have an engine for the BUGS language that
runs on Unix; to be extensible, allowing users to write their own
functions, distributions, and samplers; and to be a platform for
experimentation with ideas in Bayesian modelling. JAGS is designed to
work closely with the R language and environment for statistical
computation and graphics (http://www.r-project.org).
