Pipes are made from a variety of material. Today the most popular material are briar, corncobs and Meerschaum.
They also come in a variety of shapes and sizes, hand-made and factory made... variety to suit your style!
Long before briar was used for making pipes, stone clay and other plants were used.
Briar originates from Erica Arborea, a shrub-tree native to the Mediterranean area. However, the part of the Erica Arborea used for carving pipes is actally part of the root structure of the plant.
When starting to smoke a pipe, you just buy a pipe that you like, tobacco, a lighter and off you go. Its only later that one realises that there is a whole bunch of different recognised pipe shapes and names (all with its own story of course).
And then there is the free-hand or designer pipes that might resemble some shapes, but are mainly open to the imagination of the creator.
Like any other product, different pipe brands established itself in the market. Most notably is Dunhill. Dunhill gained reputation over many years (if not centuries) for being exquisite pipes. They come, naturally at a price, but fortunately there are many excellent competitors which will smoke good.
I bought my first pipe in 1979 and over the years, built up a collection. I wouldn't classify myself as a collector, but managed to obtain some excellent estate pipes.