Notebook/ˈnəʊtbʊk/ Definition 1 of 3Pro Tip 1/3Physical Usage Notebooks are physical items used for writing; they're tangible and can be held. Please bring your notebooks to the workshop. Pro Tip 2/3Variety of Sizes They come in various sizes, meant for portability or detailed note-taking. Her pocket notebook fits perfectly in her purse for quick notes. Pro Tip 3/3Educational Tool Notebooks are commonly used by students for learning purposes. Every student has a math notebook for homework and notes.