An online reference affiliated with the Oxford University Press (Nucleic Acids Research) that is intermittently updated. Reference a lot of database for multiple purposes (Nucleotide Sequence, RNA sequence, Microarray Data, Plant...)
The NAR online reference was a crucial contribution to centralizing databases and other bioinformatic resources, especially for its time. Although this resource very reliable and well-curated, the rule of "always use multiple resources" still applies, even for a resource that is a collection of databases.
This resource serves best the user that is seeking specific categories of databases and is familiar with those different categories. Because of the NAR online reference being more presented in more of a browser-like format, a lack of experience with field-specific terminology or knowledge may lead to this resource being less useful than other, similarly-intended resources.