So now that you know lifting won't bulk up your arms and other muscles, I should remind you that strength training has many benefits. Not only does it define your muscles, it also makes you stronger so exercise and other physical activities will seem easier. It can also strengthen your bones, which lowers your risk of osteoporosis and bone fractures. All that and it boosts your metabolism.
For tips on starting a strength training regimen,
For all these reasons, get started strength training with these six basic exercises. Then begin expanding your weight lifting horizons by doing exercises that incorporate dumbbells, machines, resistance bands, kettle bells, medicine balls, and no equipment at all. You'll become a stronger, fitter person overall, without monstrous muscles.