Yes. "Es el libro." means "It's the book." in the following context:
Mike says, "I'm looking for the book my grandpa gave me, but I lost it."
Joe says, "Oh, I think I found it." Joe holds the book up.
Mike says, "It's the book."
More often, a person would say "Es un libro." or "It's a book."
'"The Book" in Spanish is "el libro". "The book is black" would be "El libro es negro".
It Means "Which IS the Book"
It means "the book is red."
el ultimo libro del antiguo testamento es Daniel
Whose is the book? or Who does the book belong to? or To whom does the book belong?
Depending on the context, it is "mi"or "mío". Examples: "Éste es mi libro". "This is my book". "El libro es mío". "The book is mine".
El libro no es disponible en español.
"The book is blue."
para ti is Spanish for for you (informal singular you)eg.: El libro es para ti (right)eg el libro esta para ti (wrong) = the book is for you
El Libro Oculto was created in 1993.
This needs context. "Este es mi libro" means "this is my book". Under some circumstances, you can use "mío". This more commonly is "mine". "Este es el libro mío" could be translated as "This is the book of mine" or "this is my book".
"Es un libro" translates to "It is a book" in English.