I did an introductory course to Bayesian in my master's degree in Statistics. I did not understand much since it was too much in short time, very concentrated. We have covered from the most basic (bayes theorem), conjugate priors, but then moved fast to Method of composition, bayes regression, Gibbs sampler and Metropolis algorithm. I did not understand these last topics. Moreover, the software used was WinBUGS, that looked absolutely outdated and full of bugs. I would ask you, if there is any nice not outdated book about bayesian stats to read this summer. Also, I want to ask, what are the mainstream software in bayesian stats? All of them look deprecated.