Open Access Principles
The open access movement promotes the practice that scholarly research is made available online without prohibitively high subscription costs and stringent copyright and licensing restrictions. It facilitates quicker and broader dissemination of knowledge by removing the price and permission barriers to research outcomes.
Open access is compatible with features of traditional publishing such as peer review, journal prestige, and researchers' career advancement. It also offers many advantages, including:
Open-access (OA) literature is digital, online, free of charge, and free of most copyright and licensing restrictions. What makes it possible is the internet and the consent of the author or copyright-holder.
A Very Brief Introduction to Open Access by Peter Suber
"By open access, we mean its immediate, free availability on the public Internet, permitting any users to read, download, copy, distribute, print, search or link to the full text of these articles, crawl them for indexing, pass them as data to software or use them for any other lawful purpose…"