This is a practice to help you cultivate an attitude of gratitude. It involves taking time each day to reflect on the things in your life that you are thankful for. This can be done through journaling, meditation, or simply taking a few moments to think about what you are grateful for.
From Wikipedia
Gratitude, thankfulness, or gratefulness is a feeling of appreciation by a recipient of another's kindness. This kindness can be gifts, help, favors, or another form of generosity to another person.