As nouns the difference between manuscript and italics is that manuscript is a book, composition or any other document, written by hand (or manually typewritten), not mechanically reproduced while italics is (typography|pluralonly) letters in an italic typeface.
As an adjective manuscript is handwritten, or by extension manually typewritten, as opposed to being mechanically reproduced.
As adjectives the difference between novel and manuscript is that novel is new, original, especially in an interesting way while manuscript is handwritten, or by extension manually typewritten, as opposed to being mechanically reproduced. As nouns the difference between novel and manuscript is that novel is (obsolete) a novelty; something new while manuscript is a book, composition or any other document, written by hand (or manually typewritten), not mechanically reproduced.
Manuscript is a related term of manual. As adjectives the difference between manuscript and manual is that manuscript is which is handwritten, or by extension typewritten, as opposed to mechanical reproduction while manual is performed with the hands (of an activity). As nouns the difference between manuscript and manual is that manuscript is a book, composition or any other document, written by hand (or manually typewritten), not mechanically reproduced while manual is a handbook.