At it’s most basic definition, therapy is the act of caring for someone by various means. If you were to go to “physical therapy,” you would work to regain strength in your muscles and increase your ability to move, likely after an injury or a surgery.
Psychotherapy or counseling is simply having a conversation with someone who is trained to listen in a different way than perhaps your friends or family. You are likely to address a troublesome area in your life or perhaps a particular struggle, and find ways to strengthen your relationships, both with others and with yourself. Counseling is sometimes warranted because you were injured in an emotional way and are seeking ways to recover healthily. Sometimes therapy can strengthen areas of your emotional life or gain insight into life problems. Most importantly, therapy is what you want it to be with your goals in mind.