When I say it was connected to the wall, I mean it was hard-wired to a phone line in the wall, and the cord ran out a little hole in a face-plate to your telephone. Oh yes. Telephones were made of a very durable black plastic material. Just black.
You could use a telephone to make a local call to businesses, family members, neighbors or friends, but if you wanted to talk to someone in a different city, you put your finger in the hole marked 0 or Operator, and spun the dial. A friendly voice came on the line to assist you in making the connection. This, of course, cost a lot of money, so you only made long-distance calls in an emergency.
The long distance telephone operator connected your call by means of a big board with lots of lights, cords and holes, called a "switchboard." She wore a heavy headset covering one of her ears that had an attached mouthpiece speaker. When a light next to a hole on the board lit up, she answered the call by flipping a toggle switch before her, then plugging one of a set of connector-tipped brown cords into that hole. She always had a pencil in her hand, palmed when not in use, with which she noted the details of the desired call on a special card. Then, plugging the other cord of the set into the board, and using a keypad off to the side, she would "dial" the number, and when it was answered, she connected the call through by flipping another switch.
I may have the sequence of switch-flipping out of order, but that is the basic process. Correction: that WAS the process I used during my career as a long-distance telephone operator from 1966 to 1968 in Phoenix, Arizona. Both long distance and local telephone calls are much easier to make now.