Series of fantasy novels by Raymond E Feist.  A subset of the Riftwar Cycle.

The first series of novels in the Grishaverse series by Leigh Bardugo

A series of science fiction novels by Jo Clayton.  This is part of the larger Diadem Universe series.

A short sci-fi series by Robert Lory

A fantasy series by Lois McMaster Bujold.

A young adult series by the master of grimdark Joe Abercrombie.

Shawn Starbuck Westerns Series by Ray Hogan

The original series of Sherlock Holmes stories by Sir Arthur Conon Doyle.

The Shining series by Stephen King.

A fantasy series by Kenneth C Flint.

A loose fantasy dualogy by John Myers Myers

A series of young adult science-fiction novels by Brandon Sanderson.

A mega-series encompassing several other series by Gene Wolfe..

A series of short stories by Robert E Howard that takes place in the same world (although different time) as Conan.

A series of fantasy books written by George R R Martin.  Probably will never be finished.

Not for children!

A series within the Tortall universe.

A science fiction series by Jack L Chalker.

The series started in Arthur C Clark's 2001: A Space Odyssey.

The eleventh the Dray Prescot series.

A series of fantasy novels by Alan Dean Foster.

The sixth the Dray Prescot series.

A series of self published science fiction novels by Randolph Lalonde issued as "broadcasts" instead of volumes.

Cyberpunk series written in the 1980s giving birth to the term cyberspace, etc...

A series of science fiction novels by Ben Bova.

A science fiction series by G J Ogden.

Star Trek novels with slightly more pages that the Star Trek Novels and unnumbered.

Star Trek novels that began with the novelization of Star Trek: The Motion Picture in 1981 and are published periodically.

The numbered series of Star Trek: Deep Space Nine novels based on the television series.

Unnumbered Star Trek: The Next Generation novels based on the television series.

The numbered series of Star Trek: The Next Generation novels.

A series based on the Star Trek: Voyager television show.

This series is the set of Star Wars novelizations from the movies.

Star Wars novels.  This is the mega-list of Star Wars novels in chronological order within the Star Wars Universe.  I still consider these to be canon and consider all Disney Star Wars to be bad fanfic.

My personal focus on these books was everything from Star Wars - later called A New Hope - forward.

Star Wars trilogy takes place after the New Jedi Order series.

A Trilogy of novels set in the Star Wars Universe 11 ABY.

This series is set about twenty-five to thirty years after Star Wars and chronicles the New Republic's encounter with extra-galactic forces called the Yuuzhan Vong.

A science fiction series by David Gerrold.

A science fiction series by Frederick Pohl and Jack Williamson.

A series in the DDT-verse by Christopher Stasheff.

A science fiction series by Edmond Hamilton.

A series of science fiction books by Larry Niven.  These do not appear to take place in Known Space.  Sometimes referred to as the Leshy Circuit.

A series of fantasy novels written by Brandon Sanderson that takes place in the Cosmere.