Hobbies. What even is philately? Week beginning 01.01.24

What is philately? I hear you cry! Find out please and let me know. 

Here's a hint: it's something to do with hobbies. 

How many of these do you know/ do- genealogy- geocaching- sketching- kayaking- ornithology- racquetball- archery- origami- embroidery- taekwondo- yoga- quilting- campanology- astronomy- macrame- philately- calligraphy.