1: This hobby is called yarn canvasing.
2: The definition of this hobby would be to use your creativity to make different things.
3: You choose a pattern that you want to do and you get the colors of yarn you will need then you just follow the pattern.
4: The time it would take for you to make something would depend on what you were making.
5: The materials you need is the patter, your canvas, yarn, needle and a pair of scissors.
6: The estimated cost of materials would depend on how big of a project you were making.
7: I hope you like my project :)