Spellcheck is great as a quick once-over to make sure you don't have any spelling errors or to catch the words your fingers typed faster than your brain - but it is not a replacement for good proofreading.

Proofreading is essential in making sure you have theĀ right words (spellcheck won't catch the wrong words if they're spelled right!!). It's also an important punctuation check - a misplaced comma can be catastrophic!