Civil Rights
Movements, leaders, victories and the continuing fight for equality.
Explore the people, places, events, achievements, struggles and stories that shaped our journey.
Movements, leaders, victories and the continuing fight for equality.
Innovation, patents, science, technology and world-changing contributions.
Pioneers, champions, Negro Leagues, records, activism and excellence.
Meet the people whose lives, choices and achievements shaped the journey.
Black towns, communities, institutions and places where history happened.
Moments that changed communities, movements, institutions and the nation.
Wilmington, North Carolina once had a thriving Black middle class and an elected interracial government. In 1898 white supremacists used violence to overthrow that government, kill Black residents and drive many others from the city.
MORE →Reflects the personal views, recollections, and perspective of the author, Mike Davis.
This is a personal recollection on the Move fire on May 13, 1985
A persistent identifier (PI or PID) is a long-lasting identifier to a document, file, web page, or other object. The term "persistent identifier" is usually used in the context of digital objects that are accessible over the Internet. Typically, such an identifier is not only persistent but actionable:[1] you can plug it into a web browser and be taken to the identified source.
Of course, the issue of persistent identification predates the Internet. Over centuries, writers and scholars developed standards for citation of paper-based documents so that readers could reliably and efficiently find a source that a writer mentioned in a footnote or bibliography. After the Internet started to become an important source of information in the 1990s, the issue of citation standards became important in the online world as well. Studies have shown that within a few years of being cited, a significant percentage of web addresses go "dead",[2][3] a process often called link rot. Using a persistent identifier can slow or stop this process.
An important aspect of persistent identifiers is that "persistence is purely a matter of service".[4] That means that persistent identifiers are only persistent to the degree that someone commits to resolving them for users. No identifier can be inherently persistent, however many persistent identifiers are created within institutionally administered systems with the aim to maximise longevity.
However, some regular URLs (i.e. web addresses), maintained by the website owner, are intended to be long-lasting; these are often called permalinks.
People and organisations:
Publications:
Combined persistent identifier and archiving functionality is provided by services such as the Internet Archive perma.cc, archive.today, and WebCite such that anyone can archive a web page to prevent link rot of a URL.[citation needed]
Source: Wikipedia. Article content is retrieved live through the MediaWiki API.
A persistent identifier (PI or PID) is a long-lasting identifier to a document, file, web page, or other object. The term "persistent identifier" is usually used in the context of digital objects that are accessible over the Internet. Typically, such an identifier is not only persistent but actionable: you can plug it into a web browser and be taken to the identified source. Of course, the issue of persistent identification predates the Internet. Over centuries, writers and scholars developed standards for citation of paper-based documents so that readers could reliably and efficiently find a source that a writer mentioned in a footnote or bibliography. After the Internet started to become an important source of information in the 1990s, the issue of citation standards became important in the online world as well. Studies have shown that within a few years of being cited, a significant percentage of web addresses go "dead", a process often called link rot. Using a persistent identifier can slow or stop this process. An important aspect of persistent identifiers is that "persistence is purely a matter of service". That means that persistent identifiers are only persistent to the degree that someone commits to resolving them for users. No identifier can be inherently persistent, however many persistent identifiers are created within institutionally administered systems with the aim to maximise longevity. However, some regular URLs (i.e. web addresses), maintained by the website owner, are intended to be long-lasting; these are often called permalinks.
In database design, a persistent object identifier (POID) is a unique identifier of a record on a table, used as the primary key. Important characteristics of a POID are that it does not carry business information and are not generally exported or otherwise made visible to data users; as such a POID has many of the characteristics of a surrogate key. The only purpose of the POID is to act as the primary key on the table where it is defined and to be referenced as the foreign key by other tables. Because POIDs, like surrogate keys, do not carry business information, they are immune to changes in the form or meaning of business data. It can therefore make it easier to maintain relations between objects and make queries simpler.
A digital object identifier (DOI) is a persistent identifier, or persistent handle, used to uniquely identify various objects, standardized by the International Organization for Standardization (ISO). DOIs are an implementation of the Handle System; they also fit within the URI system (Uniform Resource Identifier). They are widely used to identify academic, professional, and government information, such as journal articles, research reports, data sets, and official publications. A DOI aims to resolve to its target, the information object to which the DOI refers. This is achieved by binding the DOI to metadata about the object, such as a URL where the object is located. Thus, by being actionable and interoperable, a DOI differs from ISBNs or ISRCs which are identifiers only. The DOI system uses the indecs Content Model to represent metadata. The DOI for a document remains fixed over the lifetime of the document, whereas its location and other metadata may change. Referring to an online document by its DOI should provide a more stable link than directly using its URL, but if its URL changes, the publisher must update the metadata for the DOI to maintain the link to the URL. It is the publisher's responsibility to update the DOI database. If they fail to do so, the DOI resolves to a dead link, leaving the DOI useless. The developer and administrator of the DOI system is the International DOI Foundation (IDF), which introduced it in 2000. Organizations that meet the contractual obligations of the DOI system and are willing to pay to become a member of the system can assign DOIs. The DOI system is implemented through a federation of registration agencies coordinated by the IDF. The cumulative number of DOIs has increased exponentially over time, from 50 million registrations in 2011 to 391 million in 2025. The rate of registering organizations ("members") has also increased over time from 4,000 in 2011 to 9,500 in 2013, but the federated nature of the system means it is not immediately clear how many members there are in total today. Fake registries have even appeared.
Persistent may refer to: Persistent data Persistent data structure Persistent identifier Persistent memory Persistent organic pollutant Persistent Systems, a technology company USS Persistent, three United States Navy ships
Before the 1921 destruction of Tulsa’s Greenwood District, Black residents had created a remarkable center of business and community life. The district included stores, professional offices, entertainment venues and homes owned by Black citizens. Understanding Greenwood means learning what was built—not only what was burned.
MORE →Joe Louis.