A collection of biomedical books that can be searched directly or from linked data in other NCBI databases. The collection includes biomedical textbooks, other scientific titles, genetic resources such as GeneReviews, and NCBI help manuals.


A collection of expert-authored, peer-reviewed disease descriptions on the NCBI Bookshelf that apply genetic testing to the diagnosis, management, and genetic counseling of patients and families with specific inherited conditions.

Subset of the NLM Catalog database providing information on journals that are referenced in NCBI database records, including PubMed abstracts. This subset can be searched using the journal title, MEDLINE or ISO abbreviation, ISSN, or the NLM Catalog ID.

MeSH (Medical Subject Headings) is the U.S. National Library of Medicine's controlled vocabulary for indexing articles for MEDLINE/PubMed. MeSH terminology provides a consistent way to retrieve information that may use different terminology for the same concepts.

NCBI C++ Toolkit Manual

A comprehensive manual on the NCBI C++ toolkit, including its design and development framework, a C++ library reference, software examples and demos, FAQs and release notes. The manual is searchable online and can be downloaded as a series of PDF documents.

An extensive collection of articles about NCBI databases and software. Designed for a novice user, each article presents a general overview of the resource and its design, along with tips for searching and using available analysis tools. All articles can be searched online and downloaded in PDF format; the handbook can be accessed through the NCBI Bookshelf.

Accessed through the NCBI Bookshelf, the Help Manual contains documentation for many NCBI resources, including PubMed, PubMed Central, the Entrez system, Gene, SNP and LinkOut. All chapters can be downloaded in PDF format.

National Library of Medicine (NLM) Catalog

Bibliographic data for all the journals, books, audiovisuals, computer software, electronic resources and other materials that are in the library's holdings.

A database of citations and abstracts for biomedical literature from MEDLINE and additional life science journals. Links are provided when full text versions of the articles are available via PubMed Central (described below) or other websites.

A digital archive of full-text biomedical and life sciences journal literature, including clinical medicine and public health.

A collection of clinical effectiveness reviews and other resources to help consumers and clinicians use and understand clinical research results. These are drawn from the NCBI Bookshelf and PubMed, including published systematic reviews from organizations such as the Agency for Health Care Research and Quality, The Cochrane Collaboration, and others (see complete listing). Links to full text articles are provided when available.


MEDLINE (Leasing)

NLM leases MEDLINE/PubMed to U.S. individuals or organizations.

NCBI Data Specifications

Specifications for NCBI data in ASN.1 or DTD format are available on the Index of data_specs page. The "NCBI_data_conversion.html" links to the conversion tool.

National Library of Medicine (NLM) DTDs

A suite of tag sets for authoring and archiving journal articles as well as transferring journal articles from publishers to archives and between archives. There are four tag sets: Archiving and Interchange Tag Set - Created to enable an archive to capture as many of the structural and semantic components of existing printed and tagged journal material as conveniently as possible; Journal Publishing Tag Set - Optimized for archives that wish to regularize and control their content, not to accept the sequence and arrangement presented to them by any particular publisher; Article Authoring Tag Set - Designed for authoring new journal articles; NCBI Book Tag Set - Written specifically to describe volumes for the NCBI online libraries.

PubMed Central (PMC) Open-Access Subset

The PMC Open-Access Subset is a relatively small part of the total collection of articles in PMC. Whereas the majority of articles in PMC are subject to traditional copyright restrictions, these articles are protected by copyright, but are made available under a Creative Commons or similar license that generally allows more liberal redistribution and reuse than a traditional copyright. Please refer to the license statement in each article for specific terms of use.


NIH Manuscript Submissions (NIHMS)

The NIH Manuscript Submission (NIHMS) System is used to submit manuscripts that arise from NIH funding to the PubMed Central digital archive, in accordance with the NIH Public Access Policy and the law it implements. The law and Public Access Policy are intended to ensure that the public has access to the published results of NIH-funded research.

Submission Portal

A single entry point for submitters to link to and find information about all of the data submission processes at NCBI. Currently, this serves as an interface for the registration of BioProjects and BioSamples and submission of data for WGS and GTR. Future additions to this site are planned.


Coffee Break

Part of the NCBI Bookshelf, Coffee Break combines reports on recent biomedical discoveries with use of NCBI tools. Each report incorporates interactive tutorials that show how NCBI bioinformatics tools are used as a part of the research process.

Tools that provide access to data within NCBI's Entrez system outside of the regular web query interface. They provide a method of automating Entrez tasks within software applications. Each utility performs a specialized retrieval task, and can be used simply by writing a specially formatted URL.


A service that allows third parties to link directly from PubMed and other Entrez database records to relevant web-accessible resources beyond the Entrez system. Examples of LinkOut resources include full-text publications, biological databases, consumer health information and research tools.

NCBI's monthly newsletter that provides information on new and updated databases, and software services. The News often has feature articles that highlight and demonstrate services, features, tools, and interesting data with practical examples of their use.

A specialized PubMed search form targeted to clinicians and health services researchers. The page simplifies searching by clinical study category, finding systematic reviews and searching the medical genetics literature.