Software-Based Spelling and Grammar Checkers have a Place in the Writing Process Even for Those Who Can Spell

Spelling checkers in software are good, but not perfect. They serve a very important purpose in modern writing on computers: they double-check your typing, flag words that may be spelled incorrectly, and most also check basic grammar to prevent you from from writing the same word twice in a row by accident and other common blunders. Think of your spelling checker/grammar checker as your free back-up gatekeeper, performing first, last, and in-process (depending on the brand of software you use) free help with your basic writing. However...

However, you must always remember the pithy old software engineer's warning: GIGO, which means "garbage in, garbage out". You have to spell-check your own work and/or have someone else review or do a full edit on your work before releasing it to the real audience to be a truly successful writer of any type of document. Human Intervention cane safe yew foam occidents that no computer spell checker would catch because the words are correctly spelled--they are in its database, they just don't belong in your sentence.

• If no one else can edit/proofread your work, then read it out loud (literally out loud). Wherever you have trouble reading out loud is a good signal that that's where you've made a mistake--punctuation and subject-verb agreement are the first two culprits I'd look for. However, don't think that you need to put a comma every place in your text that you are stopping to take a breath: that results in a lot of erroneous and confusing text.
• Another trick is to turn the printout upside-down literally: print out your work (double-sided is much greener), take the stack of papers and rotate it 180 degrees (so your title page is still on top but the text on it is upside-down. Now, page through your document slowly. Don't try to read the text upside-down, just look at it. Your brain will probably find mistakes you'd never have seen with the text right-side up, even after many edits/reviews.
• If you always tend to type a certain word and type another valid word instead ("brain" instead of "Brian", for instance), then set your spell-check software to always flag that word as incorrect so that you have to pause and double-check it each time you write it. Most modern spell checkers have some feature that can do this for you--read the online help system for your software for specific guidance on how to set up this functionality. Or, set the software to automatically spell out a long (or short, or hard to type) word for you, such as your company name (you type "Acme" and continue writing while the software changes "Acme" to "Acme Widgets, Inc.", the official name of your company).

Another example of "GIGO" and the dangers of relying solely on software-based proofreaders, spell checkers, and grammar checkers is that they have "garbage" in them, too.

• The people who programmed these things may have made a typo themselves.
• There are errors in every kind of dictionary, including software spelling/grammar checkers.
• The creators of the software probably created it for all forms of English, whereas you need to pick one and stay within it for consistency. For example, most spelling checkers will accept "gray" and "grey" as correct spellings for that color (and "colour", too). That's because the spelling dictionary was programmed to accept both British and American (and possibly Australian, Canadian, and Indian) English as correct. While this sounds like a good thing because you appear to be spelling fewer words incorrectly, it is actually hand-holding you and making your real audience (whichever form of English or other language they use) suffer.
• I firmly believe that there will always be people who need to print out things in order to read them, so I firmly believe that add published material should be printed on a standard printer using default settings and proofread/edited at least once. Also, some reviewers/editors find hard copies easier to deal with, therefore you will probably get more and better feedback on your work from a hard copy than you would from an online-edit of your work.

Your real audience always suffers as does your credibility when you leave the real human out of the editing/proofreading part of the writing and publishing process and end up with spelling and grammar errors. That's the bottom line. Computers assist writers a great deal, but they can't (yet) replace human editors and proofreaders.