Book of Shadows

The Book of Shadows is a book of magic owned by the Charmed Ones. It was started by their ancestor, Melinda Warren. Despite this it is dated 1693, one year after Melinda was executed for being a witch.

The Sourcebook
This is basically a condensed version of the Book of Shadows.

Year One
The Book of Shadows was found in a trunk in the attic of the manor by Phoebe. She cast the spell at the beginning of the Book that awakened their powers.

Piper's Place
Wyatt uses the Book of Shadows to cast a spell to multiply his mom so that she would have time for him. He later used it, again in order to undo the spell he cast. He did not use words either time and it is unknown if he can read, so he may not have even read the spell silently.

Family Shatters
After Paige orbs Prue to the attic of the manor, Prue goes straight to the Book of Shadows and starts looking through it for something to help. She meets Piper and Phoebe for the first time since her death when they come upstairs to check the Book as well.