A variety of exercise programs exist, all geared towards different goals. There is no perfect plan, and ultimately, you should be using a routine tailored towards your own goals. This site contains multiple exercises that can be arranged to make a guide that best suits you (just use the menu on the right under exercises to view them).
For those looking for a general idea of what a gym routine might look like, here are some generic examples:
Weight Loss Program - If you're a bit chunky, but are sure a fit body lies underneath, this program will help you unleash that inner individual.
Ab Workout Program - Effectively target the abdominal muscles and sculpt them into the toned abdomen you never thought was possible. This program is more for defining the muscles, and less for losing the fat.
Muscle Building Program - A workout program geared towards those among us who want to move up in shirt size because the muscles have simply grown too large.
Strength Building Program - An exercise routine for those of us who are happy with our muscle size and would rather have some strength to back them up.
Complete Body Program - A simple, full body workout routine for those that want to keep it simple and have no particular workout goal in mind.