English abides by the rules to use ‘er’ at the end for representing a comparative degree and use an ‘est’ at the end to represent a superlative degree.
Here are some examples:
High - higher - highest
Short - shorter - shortest
There are some exceptions such as the adjective important in comparative is ‘more important’ and in superlative it is ‘most important’. The keywords ‘more’ and ‘most’ help distinguish the comparative and superlative degrees.
Ut Italian seems to be a lot easier than the rules that English follows. Italian use "il pi_" / "pi_" (meaning "the most" / "more") nearly everywhere:
"scemo" (dumb), "sono il pi_ scemo fra gli uomini" (I'm the dumbest of men), "sono pi_ scemo di te" (I'm dumber than you).
There are also some irregularities, such as "migliore" (better or best), "peggiore" (worse or worst) etc. Regular forms exist as: "pi_ buono", "il pi_ buono", "pi_ cattivo", "il pi_ cattivo"...
Absolute superlative