Editing Ring binder (section)

==Variations==
[[File:Ringmechanik 01 (fcm).jpg|thumb|upright|left|Two ring binder lever arch mechanism]]
Binders come in many standard sizes with respect to both capacity and [[paper size]]. Countries that use [[ISO paper sizes]] (as specified by ISO 216), which is most countries, use a two- or four-hole system for holding [[A4 paper size|A4]] sheets{{Citation needed|date=April 2023}}. The [[ISO standard]] two holes are {{convert|80|mm|in}} apart, according to [[Hole punch#ISO 838|ISO&nbsp;838]]. The four-hole version has no ISO standard{{Citation needed|date=April 2023}}. The distances between holes are {{convert|80|mm|in}} (3{{nbsp}}×{{nbsp}}8).

The most common type in [[Canada]] and the [[United States]] is a three-ring system for [[Letter (paper size)|letter size pages]] ({{convert|8+1/2|x|11|in|mm|abbr=out|disp=or}}), whose size is similar to ISO 216-based A4 size. A standard {{convert|8+1/2|x|11|in|mm}} sheet of paper has three holes with spacing of {{convert|4+1/4|in|mm}}. There is a variant for [[half-letter|half-letter size pages]] ({{convert|8+1/2|x|5+1/2|in|mm|abbr=out|disp=or}}), whose three rings are {{convert|2+3/4|in|mm}} apart. "Ledger" size binders hold {{convert|11|by|17|in|cm|adj=on}} paper, and may use standard 3-ring spacing or multiple additional rings.

The distance from the punched holes to the nearest edge of the paper is less critical, since small differences do not affect the compatibility of paper and binder. Typical distance from the paper edge to the center of the hole is {{convert|0.5|in|mm}}, and typical diameter of the hole ranges from {{convert|0.25|in|mm}} to {{convert|0.31|in|mm}} in North American usage.

[[File:Image of the inside of a three ring binder.jpg|thumb|Three ring binder sprung clip mechanism]]
[[Japan]] uses a unique system, referred to as J-Binder. This system is compatible with A4 and B5 paper with different products. The A4 version uses 30 closely spaced rings, while the B5 one uses 26. Less common variants such as a 20 ring A5 version also exist.<ref>{{cite web|url=http://www.nanamipaper.com/pages/japanese-binders.html |title=Japanese Binder System |publisher=Nanamipaper.com |access-date=2019-06-17}}</ref>

[[File:Personal organizer with metallic ring binder.jpg|thumb|Personal organizer with metallic ring binder]]
Many [[personal organizer]]s and [[memorandum]] books use a six- or seven-hole system, including [[Filofax]] and [[FranklinCovey]]. Most systems have the rings on the left side of the papers as one opens the binder, but there are also binders that have the rings (concealed by the binder cover) at the top edge of the paper, reminiscent of a clipboard.

There are also various options of binder types such as the commonly used vinyl binders or customizable poly binders, turned edge binders, and sewn binders.

Most binder covers are made of three pieces, in the fashion of a [[hardback book]], with three pieces of board held together with sheets of vinyl or other materials and hinges. Materials vary widely. Some vinyl binders have a clear pocket on the outside for [[Book cover|cover pages]], and many have pockets in the inner cover for loose papers, [[business cards]], [[compact disc]]s, etc. There are also zipper binders, which zip the binder up and keep papers from falling out. Some binders are stored in matching [[slipcase]]s for greater protection; either with one slipcase per each binder, or one slipcase holding several binders.

It is also possible to insert the sheet of paper into a [[polypropylene]] [[sheet protector]]. The sheet protector has pre-punched holes, so the document can be kept untouched and unwrinkled.