I need to transfer data between the machines because I want to be able to store different type of data: it's not just "journal" in the normal sense of the word,

I need to transfer data between the machines because I want to be able to store different type of data: it's not just "journal" in the normal sense of the word, I plan to store things that pertain to my life (ie more media type than just text, and also not always info in the form of text that I can just type in). At the very least, the need for backup will require a data transfer between machine.