When choosing a bird as a pet it's vital to consider multiple factors before deciding on the species of bird, particularly noise tolerance, space, attention, and your lifestyle and home. Birds are extremely clever, provide entertainment, and can be extremely loyal and loving pets, but choosing a bird as a pet should also be a very thoughtful process in order to provide a loving and healthy environment for the bird.
As with all pets, be sure you evaluate your commitment to the bird on a daily basis and for a long-time dedication. Some species of birds, such as macaws and cockatoos, can live well over 50 years and it's difficult for them to adapt to new homes, so be ready to make the commitment for the health and happiness of the bird. Some birds require a lot more daily attention than others, so if you are away from your home a lot, you may want to consider a canary or finch.
The amount of space in your home also dictates the type of bird you should consider. The larger the bird, the larger the cage you'll need and, across the board, the more space, the better. In general, birds get a majority of their exercise in their cage, so even small birds need a decent about of space in order to allow for proper exercise. Parrots, cockatiels and budgies particularly need daily time outside of their cage for exercise, so setting up a play center or space for them is important. Since birds also like to get into mischief, be sure to “bird proof” that space. Parrots are particularly fond of chewing, so it's not only important for your home, but for the safety of the bird. Pigeons and doves need daily flights, so a flight cage, either indoors or out, is extremely important.
The amount of time you are willing to provide your bird on a daily basis should also play a key role in the species you choose. In general, many birds are social creatures and need a good bit of interaction either with you or another bird. Finches and canaries don't always like to be handled, while some other larger birds, such as cockatoos, really enjoy the interaction and “cuddling”. Many birds, such as doves, pigeons, finches, and lovebirds, need other birds to live with. If you are considering more of a flock bird such as these, it's important you consider buying more than one in order to provide your bird with an environment in which it can thrive.
Another key consideration is your tolerance of noise and mess. Some birds are quiet and non-obtrusive, while others like to screech, get rowdy or just sing. Macaws for example, can be very loud and require a great deal of attention. Birds can also be really messy, because their food can get all over the place (it usually doesn't stay in the cage) and others lose a good bit of feather dust regularly (most notable in cockatiels and cockatoos).
A new bird takes patience and kindness in order to make them comfortable in their new home. If you are ready for the commitment and time a bird requires, then you may have a loving and loyal companion to add to your home.