A very powerful hooked beak is used to open nuts and seeds. This amazingly powerful beak is also used to grasp branches and perches when climbing from one to the other. Cockatiels use their beaks along with their feet to pick things up, eat, and climb. They have two toes at the front of their feet and two toes at the back. The same book says they are capable of hanging upside down using only one foot, and they can perform amazing maneuvers.
Cockatiels are social creatures, and they require interaction with either a human or another bird.
It says a second cockatiel can be introduced after the bird has formed this bond. It recommends a cage that is at least eighteen square inches in size with bar openings no greater than three quarters of an inch apart. Suggestions for lining the bottom are shavings of aspen or pine, paper toweling, black and white newsprint, or brown bags cut to size. Perches of varying diameters should be available to provide exercise for the bird's feet. Branches, soft cotton rope, and cement perches are all good choices.