My favorite genre is military science fiction. If any of the books i list are not military science fiction i'll make a note of it.

Almost anything by Heinlien is good, although, one of his most famous, A Stranger In A Strange Land was jsut plain wierd.

One of his best was Starship Troopers, and before you say"i saw the movie", just shut the hell up. The movie was a tragedy!! The only thing it had in common with the book was the title.
*****

David Weber has a series called the Armageddon Inheritence which pretty much rocks. It starts with Mutineer's Moon. Once you read this one you're hooked.
****

For funny science fiction try Robert Asprin's A Phule's Company. or Harry Harrison's Stainless Steel Rat series. Both of these are funny.
*** .5

Isacc Asimov does Foundation . Look for this to be a movie eventually.
***

Eric Flint 1632. Time travel novel about a bunch of West Virginians(?) going back thru time space to 1632 Europe.

John Ringo also does some cool sci-fi military. He has done several books with David Weber. A Hymn Befroe Battle is fun, and another good one is March Upcountry.
****

FANTASY
G.R.R. Martin's Series A Song of Ice and Fire starts with A Game of Thrones this is a good series though a bit lewd.
****

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I do not think that word means what you think it means--Inego Montoya