Ring binders have been around for a lot longer than most people realise. They were invented in Germany in 1886 by Friedrich Soennecken. In November of that year he registered the patent for his new invention of Papierlocher für Sammelmappen, or hole punch system. There have been further developments since that time, but by and large, ring binders are pretty much the same today as when they first started out.

Ring binders, also sometimes known as files, are essentially folders that can hold sheets of paper through ring clamps that go through pre-punched holes in the paper sheets. The retaining clamps are usually circular, but can be D-shaped. They are usually two-hole or four-hole binders designed for the A4 size of paper sheet. However, in the USA and Canada, a three-hole system is the most common. This is designed to accommodate the letter size paper sheet.

Ring binders are made to accommodate standard paper sheet sizes, usually the A4 size. The capacity of a ring binder is not an absolute, but most are designed to hold a very generous amount of sheets that is usually enough for most needs. Adding or removing sheets of paper is managed by simply pulling apart the retaining rings that go through the pre-punched holes in the paper. This is usually sprung to hold it in a closed position, and it requires a small effort to pull it apart. In the open position, sheets of paper can be threaded through the rings to add them to the binder, or unthreaded to remove them. Snapping the rings together again secures the binder once more.

The covers of ring binders are made up of three pieces, a front, back and spine. They can be of PVC, which is probably the most common, paper over board, which offers quality at an affordable price, or recyclable polypropylene, which offers a very wide range of options in terms of colour, finish and design.

Ring binders can be found in every office and in most homes. They offer a degree of versatility that few other systems can offer. They are simple to use, inexpensive to purchase, they are available in a wide range of options, and they generally have a long shelf life, making them ideal for any situation where printed paper sheets need to be collated and organised.