> For the complete documentation index, see [llms.txt](https://revhero.gitbook.io/revhero-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://revhero.gitbook.io/revhero-docs/support/glossary/i.md).

# I

Hotel and revenue management terms beginning with I.

## IATA (International Air Transport Association)

The trade association of airlines that fly international routes. It sets industry standards, runs training and provides services to its member airlines.

**See also:** [GDS](/revhero-docs/support/glossary/g.md) · [Hotel market segments](/revhero-docs/support/glossary/h.md)

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## IDS (Internet Distribution System)

The set of online routes through which your rooms and rates are sold — websites, OTAs and other digital platforms.

It lets you list the same rooms across many online channels at once.

**See also:** [Electronic distribution](/revhero-docs/support/glossary/e.md) · [OTA](/revhero-docs/support/glossary/o.md) · [Distribution channel](/revhero-docs/support/glossary/d.md) · [GDS](/revhero-docs/support/glossary/g.md)

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## Incremental Revenue

The extra revenue an action earns, above what you would have earned without it. It is how you measure a promotion or an upsell.

**Incremental revenue = revenue with the action − baseline revenue**

A promotion brings in €10,000. Without it you expected €7,000. Incremental revenue = €10,000 − €7,000 = €3,000.

**See also:** [Conversion rate](/revhero-docs/support/glossary/c.md) · [Ancillary revenue](/revhero-docs/support/glossary/a.md) · [Upsell](/revhero-docs/support/glossary/u.md) · [Demand generators](/revhero-docs/support/glossary/d.md)

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## Independent Hotel

A hotel owned and run on its own, with no chain or franchise behind it. It sets its own brand and its own way of working.

**See also:** [Chain hotel](/revhero-docs/support/glossary/c.md) · [Hotel franchise](/revhero-docs/support/glossary/h.md) · [Hotel group](/revhero-docs/support/glossary/h.md)

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## Interface

A technical connection between two computer systems that lets them exchange data directly, with no person in the middle.

**See also:** [Direct connect](/revhero-docs/support/glossary/d.md) · [Channel manager](/revhero-docs/support/glossary/c.md) · [PMS](/revhero-docs/support/glossary/p.md)

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## Inventory

The rooms you have available to sell across all your channels. It is the total number of saleable room nights.

A hotel has 100 rooms: 40 Double, 30 Twin, 20 Superior and 10 Suite. If 2 Double rooms are out of order, the inventory available to sell that night is 98.

Inventory is the number you divide by when you calculate occupancy and RevPAR. Managing it — overbooking limits, allotments and restrictions — is a core part of revenue management.

**See also:** [Room type](/revhero-docs/support/glossary/r.md) · [Hotel capacity](/revhero-docs/support/glossary/h.md) · [Occupancy](/revhero-docs/support/glossary/o.md) · [Overbooking](/revhero-docs/support/glossary/o.md) · [Allotment](/revhero-docs/support/glossary/a.md)

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