Very Computer

  I'm new around here so excuse me if I'm repeating something or if this
isn't the right place for the questions I have.

  I'm trying to learn something about syntactical correctors, that is,
  programs that check and correct the syntax of a phrase (sounds
redundant
  but I'm not sure if that's the way it is called in english).

  - What kind of formalisms are used?

  - What are the most appropriate languages to build one (are there any
    specific environments)?

  - What kind of manpower does it take to develop a corrector?

  - What's available in the market?

 Please answer to my e-mail adress.

    Thank for your attention and thanks in advance for possible answers.

                                        Emanuel Ventura