OK, I'll bite.
How often you should exercise depends to a large degree on your current level of fitness. Beginners need rest days. The Couch to 5K programme for people who want to start running, for example, suggests three days of exercise per week, with four rest days. As you get fitter, you can exercise more frequently, up to 5 or maybe 6. If you really want to do something every day, then a couple of your days need to be something different, and/or lighter, from your main exercise. This helps avoid overuse of any particular muscle group. If you normally run - then swim. If you normally cycle, then get on a rowing machine, or just go for a brisk walk.
One golden rule is that if you are doing strength/resistance training, you should not work the same muscle group on 2 consecutive days. When you strength train, you actually damage the muscle fibres, and they need time to repair. The harder you train, the more rest you need. Rest is just as much part of your programme as your workout.
If you are looking for the best bang for your buck in terms of getting results from your training, then you need strength training first, followed by some intermittent high intensity intervals of cardio, followed, if you must, by some steady state cardio.
Good luck, and don't hurt yourself out there,
Barbara