Leg curls isolate your hamstrings and stimulate them for maximum muscle growth and building strength in that region.
Leg raises are an excellent exercise that engages your abdominal muscles while building strength in that region. It's also excellent for lower abs.
These exercises target the calf muscles and promote hypertrophy without stressing the upper legs and growth in that region while giving them the chiseled look.
Leg presses are an excellent way to engage the legs without stressing out the back or any other regions of the body.
The barbell curl has stood the test of time as a great isolation workout that works both the upper arms and forearms to build strength and stimulate muscle growth in that region.