From the golden age of cycling in the 1890s onwards, cyclists have sought ways to adapt their bicycles in order to carry cycling paraphernalia and personal possessions.
The basket over the handlebars was one solution, but this, though handy for shopping, was hardly practical for routine commutes or long-distance touring, where capacity and protection from the elements were crucial. Here the pairs of saddlebags use on horses were the natural inspiration in its early days. After all, the bicycle was widely know as the mechanical horse; and so the bicycle pannier was born.
Modern panniers are usually attached to the rear of the bicycle, hooked onto the luggage rack by an elastic mechanism or a latch; occasionally another pair of panniers is carried at the front as well. Panniers are usually made from waterproof canvas or nylon, thus protecting the contents from the rain. Contemporary versions for the commuters are made for carrying laptops and office clothes.
The messenger bag used by couriers is yet another solution to the problem of the bicycle-adapted bag.