Digital Libraries I: Library Automation and its Standards; Barcode, RFID, QR Code, Biometric and Smart Card Technologies; Digitisation; Digital Libraries, their Architecture, Standards, Formats and Protocols, and the DOI; and Digital Preservation

The ISBN-13 printed as an EAN-13 barcode ends in a check digit that lets systems catch keying errors. The first twelve digits are weighted alternately 1 and 3, the products are added, and the check digit is the amount needed to reach the next multiple of 10. For 978-0-306-40615-?, the weighted sum is 9 + 21 + 8 + 0 + 3 + 0 + 6 + 12 + 0 + 18 + 1 + 15 = 93; the next multiple of ten is 100, so the check digit is 7 and the ISBN is 978-0-306-40615-7. The ISBN has had 13 digits since 1 January 2007; the ISSN has 8 digits and uses a different, modulus 11 check, which is why an ISSN can end in X.

Digitisation converts analogue materials, texts, images, maps, audio and film, into digital form, to widen access, reduce handling of fragile originals and support preservation. Planning defines the purpose and audience, checks copyright, estimates cost, and sets technical standards and metadata. Selection weighs intellectual and historical value, demand, uniqueness, physical condition (fragile items may need special handling), copyright status and whether the item has already been digitised elsewhere. Hardware includes flatbed scanners, overhead (planetary) book scanners that capture bound volumes face up without damaging spines, high-resolution cameras, and microfilm and slide scanners. Software handles image capture, processing, optical character recognition (commercial tools and open source ones such as Tesseract, which supports many Indian scripts), metadata creation and delivery through a digital library system.

• Process: select and prepare items (conservation checks, collation); capture archival master images, typically uncompressed TIFF at 300 to 600 pixels per inch depending on the material; check quality; create smaller access copies (JPEG, PDF); run OCR for searchable text; add descriptive, structural and administrative metadata; store masters with backups; and publish through a digital library platform.
• Formats: TIFF and JPEG 2000 for image masters, PDF/A (ISO 19005, first part 2005) for archival documents, WAV for audio masters, and open, well-documented formats wherever possible.
• Issues: copyright and permissions; high cost and staff time; selection bias; OCR accuracy for Indian scripts and old print; long-term sustainability; and the fact that digitisation is not preservation unless the digital files are themselves preserved.

The idea of the digital library runs from Vannevar Bush's Memex (1945) and J. C. R. Licklider's Libraries of the Future (1965) to the US Digital Libraries Initiative, funded from 1994 by the National Science Foundation, DARPA and NASA at six universities (a Stanford project in it is where the Google search engine began), and its second phase from 1998. The Digital Library Federation's 1998 definition describes digital libraries as organisations that provide the resources, including specialised staff, to select, structure, offer intellectual access to, interpret, distribute, preserve the integrity of and ensure the persistence over time of collections of digital works, so that they are readily and economically available to a defined community. Characteristics are digital collections, access at any time from anywhere, simultaneous use by many, full-text searching and linking, and services beyond physical walls. Types are digitised collections, born-digital collections, hybrid libraries that combine print and digital, and virtual libraries that give access to resources held elsewhere.

The Digital Object Identifier (DOI) is a persistent identifier managed by the International DOI Foundation (founded 1998) and standardised as ISO 26324 (2012). It is built on the Handle System and has a prefix beginning "10." that identifies the registrant and a suffix chosen by the registrant, as in 10.1000/182. Resolving the DOI through doi.org sends the user to the current location of the object, so a citation keeps working when the publisher's website changes. Registration agencies assign DOIs: Crossref (2000) for scholarly publications, DataCite for research data, and others.

Digital objects are more fragile than paper. Storage media decay and fail; hardware and software become obsolete, so files cannot be opened; formats go out of use; links break; and without documentation the context and authenticity of a file are lost. Digital preservation is the set of managed activities that keep digital content accessible, usable and authentic for as long as it is needed. Its standards are the OAIS reference model (Open Archival Information System, from the Consultative Committee for Space Data Systems; ISO 14721, first 2003, revised 2012), which defines six functional entities, ingest, archival storage, data management, administration, preservation planning and access, and three information packages, the submission, archival and dissemination packages (SIP, AIP and DIP); the PREMIS data dictionary for preservation metadata (2005); ISO 16363 (2012) for auditing and certifying trustworthy digital repositories, derived from the earlier TRAC checklist; and PDF/A for archival documents.

Projects include, internationally, LOCKSS and CLOCKSS for e-journals, Portico (2005) as a dark archive for scholarly content, the Internet Archive (1996) with its Wayback Machine for web archiving, and UNESCO's Charter on the Preservation of Digital Heritage (2003); and in India, the Centre of Excellence for Digital Preservation at C-DAC, Pune, under the national digital preservation programme, which has developed standards and tools for Indian archives, alongside repository-level preservation by national institutions.