Ligaments bind bone to bone and tendons bind muscle to bone. A ligament is a fibrous connective tissue which attaches bone to bone, and usually serves to hold structures together and keep them stable. Bones are connected together by fibrous tissues called ligaments. Ligaments give joints stability and prevent them from moving abnormally. A severe injury to a joint, more than the ligament can withstand, is a tear of the ligaments called a sprain. Muscles are attached to each other and to bones by fibrous cords called tendons. Overuse or injury of a muscle or a tendon is called a strain. Tendinitis is inflammation, irritation, and swelling of a tendon, which is the fibrous structure that joins muscle to bone. In many cases, tendonosis (tendon degeneration) is also present. A tendon is a fibrous connective tissue which attaches muscle to bone. Tendons may also attach muscles to structures such as the eyeball. A tendon serves to move the bone or structure. The symptoms of a sprain or strain are pain, swelling and/or loss of normal function of a joint, muscle, tendon, or ligament. Ligaments and tendons can be stretched, torn, or in some cases, may be injured in association with a fracture. Common sprains and strains may be due to sudden movement (e.g. a fall, a twist, or sudden vigorous exercise) for which the body has not been prepared. Muscle, tendon, or ligament injuries typically have a more rapid and localized onset of pain and take longer (weeks or months) for full recovery. I can personally tell you that Achilles tendinitis is inflammation of the large tendon at the back of the leg that attaches the calf muscles to the back of the heel bone. Under too much stress, the Achilles tendon tightens and works too hard. The pain is almost unbearable. You can strain a tendon but you can rupture a ligament and the pain and swelling from that is very severe and is disabling. From various net sources.

a tendon connects muscle to bone. a ligament bone to bone. so if you a tendo injury would hurt with a stretch to teh muscle and ALSO by contracting that muscle. a ligament in theory would only hurt when stretched or palpated (pressed on). some ligaments also do not heal after injury, such as the ACL if torn severely. tendons will heal most of the time, unless completely torn. in that case surgery is required to suture it together.