I am an habitual user of a fountain pen. It is the only writing implement that I carry with me since I enjoy writing with a fountain pen and because I can keep track of one pen but no more than one. I have used it, and its predecessors, to make notes in a series of forty notebooks that stretch back to when I started as a research assistant forty years ago. I used to record laboratory results in my notebooks but nowadays I have a research team who perform all of the work in the laboratory. I still use my pen and notebook to record meetings, ideas and notes on papers. I find the process of writing notes by hand to be conducive to both remembering detail and connecting fragments of information into new thoughts and ideas. I am not alone in having these experiences. Researchers have found that taking notes by hand improves the performance of students in answering conceptual questions compared to students who use a laptop to take notes. When you write on a laptop, it is easy to delete words and re-start a sentence, whereas to create a coherent set of notes in a book you need to craft a sentence prior to committing pen to paper. Perhaps the latter process allows a more persistent assembly of neurons to be formed in your brain [see ‘Slow deep thoughts from a planet-sized brain‘ on March 25th, 2020]; or maybe it is just the irregular spacing between handwritten words which creates a more distinct pattern that can be more readily recalled than the repetitive single spaces in typed text. I certainly feel there is a connection between recalling the image of a page from my notebook and remembering the content even though I cannot usually read the words in my mental image.
Crumb RM, Hildebrandt R & Sutton TM, The value of handwritten notes: a failure to find state-dependent effects when using a laptop to notes and complete a quiz, Teaching of Psychology, 49(1):7-13, 2022.
It is also way easier to make a drawing or schedule or schema with just a pencil(or fountain pen) on paper then it is on a computer. It takes quite a effort even to create the simplest of things on a computer screen with a mouse. It helps you to visualize your thuoghts in a simple and understandable way.