Community attribution advice
This document is an attempt to summarize the expectations the OpenStreetMap hobby craft mapper community has for OSM data users regarding the attribution required by the OpenStreetMap license.
In line with the general culture of OpenStreetMap it does not try to provide firm and inflexible corset of step by step instructions how to attribute but instead gives advice on how the community views attribution and allows data users to meet these expectation under their own responsibility.
Views within the OpenStreetMap hobby craft mapper community on what kind of attribution is or should be necessary varies a bit. This advice in meant to describe the consensus position in the sense that attribution designed based on this advice will find a broad consensus among mappers to be acceptable. To what extent you can practically get away with lesser attribution - either legally or socially - is outside the scope of this document.
Why we require attribution
OpenStreetMap data is produced and maintained primarily by volunteer mappers. Data users do not need to provide any financial or other form of remuneration to mappers for using their work - except attribution. Attribution of use of OpenStreetMap data is the acknowledgement you need to give to the mappers for the work they provide and that you are otherwise free to use. By doing so you express your respect and appreciation of the work of millions of OpenStreetMap contributors that they allow you to freely use. Not all OpenStreetMap mappers individually make their contribution contingent on data users providing attribution but we all expect this attribution to be provided by all data users as the collective position of the whole mapper community based on which we have chosen the license for our data.
What we mean by attribution
What we understand attribution to mean is formally stated in section 4.3 of the ODbL:
"However, if you Publicly Use a Produced Work, You must include a notice associated with the Produced Work reasonably calculated to make any Person that uses, views, accesses, interacts with, or is otherwise exposed to the Produced Work aware that Content was obtained from the Database, Derivative Database, or the Database as part of a Collective Database, and that it is available under this License."
What we mean by this is that the criterion for a valid attribution is if it effectively makes the user aware that OpenStreetMap data licensed under the ODbL is used. In case of an interactive map the widely used form of attribution shown in one of the corners of the map can fulfill this requirement when displayed at least in a size and prominence comparable to other content displayed on the screen. But it can also fail to do so if displayed right next to a blinking ad catching all the user's attention for example. It is the responsibility of those who publicly use OpenStreetMap data to ensure the attribution fulfills its purpose and makes the user aware of the provenience of the data.
You need to actively communicate this information to the user to meet these requirements. Merely making it available to users actively seeking this information is not enough.
While we require you to attribute use of OpenStreetMap data we of course also want you to specifically only attribute use of OpenStreetMap data to us and not any other geodata you might use in addition. Therefore you should be specific about what elements of your map or other work are based on OpenStreetMap data in your attribution.
In interactive applications of OpenStreetMap data like interactive maps it is accepted among mappers if the information about the nature of the OpenStreetMap data license is provided through a link in contexts where links are a generally expected method to provide more detailed information. Condition for this is that the medium of display allows showing the information behind the link in a form readable for the user. This is in particular to be considered for applications that are likely to be used offline.
The traditional form of attribution text in interactive online applications with a link to https://www.openstreetmap.org/copyright is "© OpenStreetMap contributors". This emphasizes the above mentioned purpose of the attribution acknowledging the work of the mappers. The shortened "© OpenStreetMap" is typically also accepted though some mappers prefer the longer and more specific version.
Note making the user aware does not require continuously nagging them about it. In a single user viewing situation it is perfectly all right - and in some cases even desirable - to allow the user to hide the attribution after seeing it.
In non-interactive use cases, like for example a printed map, you have - in addition to attributing the OpenStreetMap contributors - to inform the user that the data is available under the ODbL. Printing a link or a barcode with the link is not sufficient for that. One possible English language attribution text for a map would be
"Contains information from OpenStreetMap, which is made available at openstreetmap.org under the Open Database License (ODbL)"
If you use other data in addition to OpenStreetMap you should specify the scope of OpenStreetMap data use in the attribution.
As an OpenStreetMap data user you might still be unsure how to specifically design your OpenStreetMap attribution. As long as you follow the principles outlined above and make a honest and generous effort in meeting the attribution requirement and this way expressing your respect and appreciation of the work of the mapper community you will not run into problems with that and community members will usually be glad to help you with specific suggestions if necessary. Be proud in using OpenStreetMap data in communication with your users and the OpenStreetMap community will be grateful and supportive for you doing so.