Levels of Kashrut
There are four general categories of kashrut regarding STa”M.
Pasul (Invalid) – This category refers to STa”M that does not meet the minimal halachic requirements to be used. A bracha cannot be said and one does not fulfil his obligation with it.
Kasher Bediavad (Ex post facto) – STa”M regarding which one fulfils his obligation with, although may not be used if there is another that is kasher lechatchilah.
Kasher Lechatchilah (In the first instance) – STa”M that has all the halachic requirements to be able to make the appropriate blessings and fulfill one’s obligation with it.
Mehudar (Beautiful) – Mehudar denotes a level of kashrut that goes above and beyond that which is required by the letter of the law. Things such as uniformity in the writing, stringencies and STa”M that is aesthetically pleasing are all apects that can attribute STa”M to a more mehudar level. There are many levels in this category and sometimes criteria by which STa”M is deemed more mehudar may vary according to different halachic authorities.