During the days of film, good panoramas required a tripod-mounted camera for stability, an accurate protractor, careful exposure of each photo to ensure consistent lighting, a lot of cropping to remove any overlapping portions between adjacent images, and scenery that (preferably) didn't move. Today, most digital cameras include a "panorama" option to guide you through the entire process, and there's plenty of excellent computer software available capable of automatically analyzing and accurately stitching a consecutive series of photos into one seamless image.
Here are a few examples of the many panoramic images I've taken over the years. Digital panoramas were constructed by using the "Panorama" feature of my Canon digital camera and then stitched together using Hugin, a full-featured, comprehensive, and free panorama creation software package. Older 35mm film panoramas, originally constructed using scanned photographs and Apple's long-discontinued "Quicktime VR Studio" software, were reconstructed by scanning the negatives and using Hugin.
Click on any image for a much larger version. Note that all images are watermarked.