What is the use of Fat burner pills?

People adopt many ways to reduce body fat. Some choose to do hard work by following some exercises and diet schedules where some are not comfortable in doing this kind of heavy stuff and adopt ways like weight loss drinks and fat burner pills.
How do fat burner pills work on your body?
• They work by boosting your metabolism which tends to burn more fat.
• Suppress appetite, so you eat less and
• Reduce absorption of calories.
Some fat burner pills available in market are - PhenGold, Instant Knockout, capsules by HK Vitals etc.