Much of this can still be considered canon where it does not contradict later established information.

This show is considered canon, despite a few continuity errors with the earlier series.

These books, as with most of the other Trek novels, are not considered canon.

The events presented in the film are not considered canon to either of the two series.

Although the books are not considered canon, they do give plausible reasons.

These appearances, though a part of official merchandise, are not considered canon.

These characters aren't considered canon, as they were only proposed.

It is unknown if any of these stories are to be considered canon.

Thus, each man was able to do what he pleased with the series, while still having one another's work distinct and be considered canon.

Several of the stories are humorous in tone, but the more serious ones may be considered canon.