Co:Writer is a type-and-speak writing assistant with intelligent word prediction, designed to help users write complete and correct sentences with very few keystrokes. It is usually used in combination with another application, such as a story-writing program or a word processor.

When a user begins to type, Co:Writer will predict and offer a set of possible words from its built-in customizable dictionary. The user can then easily choose the best word with one keystroke or a mouse click. This reduces typing and can increase the user's vocabulary.

To aid users in selecting words and writing sentences, Co:Writer can speak the guesses automatically or on an as-needed basis. Co:Writer can also speak the letters or words as they are entered and speak the finished sentence.