Corrector and substitutions are not something that I dislike excessively, since for certain programs they come quite well and can make your work faster, but there are other times that they get a bit in the way.
In any case, if you are one of those who like to have it always activatedYou can do it using three simple terminal commands that I leave here and that I have seen in Mac OS X Hints:
defaults write -g WebAutomaticTextReplacementEnabled -bool true defaults write -g WebAutomaticDashSubstitutionEnabled -bool true defaults write -g WebContinuousSpellCheckingEnabled -bool true