Lattice is a relatively low level package for plotting in R. It is very powerful, but often requires a lot of tweaking to get the results just right. Many recent packages ([wiki:HlpLab/R/MCMCPackage MCMCPackage], [wiki:HlpLab/R/MCMCPackPackage MCMCPackPackage], [wiki:HlpLab/R/LME4Package LME4Package], [wiki:HlpLab/R/DesignPackage DesignPackage], etc.) build their graphics on top of Lattice.