What is journaling?
The translation of journal is diary. Here you define what you want to record.
What you record and how is different for everyone. For some this is a description of the day, emotion or quote. For the other an agenda, goals or habits.
Some do this through writing, photos or pretty papers. The other by drawing, painting, or stamping.
The possibilities are endless! As long as it's yours and it helps you achieve what you want. It is nice to get inspiration and possibly use nice things.