essay is usually a short piece of writing which is quite often written from an author's personal point of view. Essays can consist of a number of elements, including: literary criticism, political manifestos, learned arguments, observations of daily life, recollections, and reflections of the author. The definition of an essay is vague, overlapping with those of an article and a short story. Almost all modern essays are written in prose, but works in verse have been dubbed essays (e.g. Alexander Pope's An Essay on Criticism and An Essay on Man). While brevity usually defines an essay, voluminous works like John Locke's An Essay Concerning Human Understanding and Thomas Malthus's An Essay on the Principle of Population provide counterexamples.

Blacklight is an open source OPAC (online public access catalog). That means libraries (or anyone else) can use it to allow people to search and browse their collections online. Blacklight uses Solr to index and search, and it has a highly configurable Ruby on Rails front-end. Currently, Blacklight can index, search, and provide faceted browsing for MaRC records and several kinds of XML documents, including TEI, EAD, and GDMS. Blacklight was developed at the University of Virginia Library and is made public under an Apache 2.0 license.

There sure is! You can see the Blacklight plugin as it looks out of the box at http://demo.projectblacklight.org/. You can also see a list of working instances on the sample_installations page.

You can download the latest release from our download page or you can check out the very latest code from github at http://github.com/projectblacklight/blacklight. The prefered method is to run the template based installer details of which can be found http://blacklight.rubyforge.org/

The best place to find all the dependencies is on the pre-requisites_and_architecture page.

Blacklight is a rails engines plugin. That means you need to install it inside a ruby on rails application. Once you install the plugin into a blank rails application, you'll have all of the default plugin behavior. You can see what this will look like at http://demo.blacklightopac.org. Then you can overload behaviors, look and feel as you like in the container application. You can see an example of a very overloaded plugin at UVA.

The easiest way to get started is to install blacklight. Follow the instructions at http://github.com/projectblacklight/blacklight/blob/master/README.rdoc.

There used to be a known dependency incompatibility that prevented Blacklight from installing on windows (specifically, the bcrypt library). This dependency has been removed, so we currently know of no reason why it could not be installed on windows. However, most of the project's developers work on linux or OSX, and we don't know of any successful windows installations. If you do one, please let us know!

Open Library has a great collection of real marc records donated from libraries around the world. If you don't have MaRC records from your own library to play around with, or if you just want a larger sample set, you can download some here: http://www.archive.org/search.php?query=mediatype%3A%22data%22%20MARC

Z39.50 is a standard that “specifies a client/server-based protocol for searching and retrieving information from remote databases.” Blacklight is not a standard for data exchange, it is a front-end application designed to let a library index and search data from a variety of sources. You could conceivably use Z39.50 data sources in Blacklight, and some institutions are doing this particularly to query Integrated Library Systems for availability data.

Blacklight uses solr as its data index. Blacklight is agnostic as to how that solr index gets populated. However, one excellent way to index lots of marc records into solr quickly is to use SolrMarc. Some of the same people are active in both projects, e.g, Bob Haschart from UVA and Naomi Dushay from Stanford University. SolrMarc is not a Blacklight-specific project, it is also used by VuFind and other projects, and is a separate project that exists in its own right.

Click the login button at the top right corner of the wiki. You can use any OpenID to log onto the wiki and edit it. There is a list of OpenID account providers here. Chances are, you already have an account you can use.

Install the software, join the mailing list, augment the wiki. We are trying to create an open, welcoming community, and newcomers are welcome. If you're new to ruby on rails or some of these other technologies, that's okay, just jump in and we'll do our best to help you get started. Everyone here is united by a desire to provide a better search and browse experience for library users.

Check your ruby log files, in BLACKLIGHT_HOME/log/development.log or production.log depending on what environment you're running. If you see an error message like Net::SMTPFatalError (550 5.0.0 Access denied your server has mail delivery disabled. Fixing this will depend on your operating system. For Fedora Core Linux you can fix it by adding the line sendmail: ALL to /etc/hosts.allow, but if you do this be sure you have a good firewall set up, and use abuse.net's tools to make sure you're not setting up a spam relay: http://www.abuse.net/relay.html