Our hands write, pick up things, hold, touch, feel. They are records of things we have done, mistakes we've made, from touching heated iron to being cut on the razor edge of a paper. They mark the path we've taken through various stages of life. They bear the scars we've forgotten all about.
You can tell more about a person from their hands than anything else. Those who have a hard life have rough hands, scarred and marked and lined; their nails are chipped and dirty, their skin dry and hard. Those who have had less troubles, and not had to work so hard have smooth hands, with only the smallest of marks. All you need to know of a person is written in their hands. There is a basis to the art of palmistry after all.
Don't take them for granted; they aren't there to be bashed and abused by your carelessness. One day, there will be someone who holds your hand, and be able to tell from the feel of them alone what kind of person you are, whether writer, artist, musician or business person, accountant, or even parent.