The StrongLift 5x5 Workout

There are myriad exercise programs and lifting routines one can use to increase fitness and muscle mass. It can seem a daunting prospect wading through various data (unless you have a lot of knowledge or a personal trainer) to try and find a plan that's right for you and your goals. 
The StrongLift 5x5 (5x5) is a simple but effective plan that could be just what you are looking for. It can be tailored to your specific needs and tweaked to fit in with your schedule. Its beauty, however, lies in its simplicity. 
We all know that some plans are so detailed and contrived that we need to stop and read up on what we are meant to be doing next mid workout. This is obviously not ideal as we need to be working at an optimal level with proper timed rests to gain the best payoff and results for our time and efforts. StrongLift 5x5 has this covered. 
The premise of 5x5 is five reps and five sets of each exercise, with a 90 second rest between sets and a three minute break between exercises if one's goal is strength or a 90 second break between exercises if one's objective is gaining size. It is considered an ideal training regimen for someone who has been lifting higher reps for a while before embarking on a serious powerlifting program.
Ideally, to make the most of 5x5, one should use the maximum weight they can lift. When one is able to do five sets of five with that weight should then be increased by 5 - 10% until one can again do five sets of five. Never increase the weights in larger increments as this can hamper progress and cause injury.
5x5 can be done either as a split or full-body routine. One shouls aim to do a full-body workout 2-3 times a week or one can alternate upper body one day and lower body the next; the choice is yours. 
Below are a couple of routines you might try: 

Full-body workout: Three times a week
Monday: Bench press, bent-over rows, squat and deadlift.

Wednesday: Weighted dips, weighted chin-ups, deadlift and hanging leg raises x2.

Friday - Incline bench press, front squat, glute/hamstring raise; renegade row (with dumbbells or kettlebells), and saxon sidebends. 

Split routine: Six times a week 
Monday/Thursday - (chest/back): a) Incline bench press, wide grip pull-up (palms facing you), weighted rope crunches; b) Chest dips, one-arm dumbbell rows, weighted lying leg raises.

Tuesday/Friday - (legs): a) Squats, lying leg curls, calf raises; b) Leg press, stiff-legged deadlifts, calf press.

Wednesday/Saturday - (shoulders/arms): a) Upright row; close-grip bench press, preacher curls; b) Rear delt rows, triceps pushdowns, incline hammer curls.