Open Access Models

Open Access (OA) models can be divided into several main categories, each with its unique features:

Gold Open Access:
• Publications are freely available in journals that are often funded by article processing charges (APCs) paid by authors or their institutions.
• Gold OA ensures that all articles are accessible to everyone at no cost.

Green Open Access:
• Authors publish their works in institutional or thematic repositories, allowing free access to them.
• This typically concerns preprint or postprint versions of articles.
• Many journals allow this practice, although the conditions may vary.

Bronze Open Access:
• Publications are available for free but under certain restrictions, such as requiring registration or being accessible only within specific time frames.
• This is often used in some journals that offer access to articles after a certain period.

Black Open Access:
• Publications that are shared illegally, for example, through piracy sites.
• This approach is unethical and illegal and does not support the idea of open access.

Hybrid Open Access:
• Journals that are primarily subscription-based but offer the option to publish selected articles in the OA model after the author pays a fee.
• This allows part of the content to be accessible to a wider audience while the rest remains paid.

Each of these models has its advantages and disadvantages, and the choice of the appropriate one depends on the publication's goals, funding, and authors' preferences. An open approach to publishing can significantly influence the availability of knowledge and accelerate the advancement of science.