We recommend having your journal as fully open access, meaning that readers can freely access, download, copy, and distribute all journal content as long as credit is given to the authors (for more details, see the Copyright and Creative Commons section). In order to provide equitable access to the journal content, your journal should not require a subscription or any other form of payment either directly from readers or through their university or library, to access content. The Right to Research Coalition has a statement on the ways that open access to research benefits society: Why Open Access?.
Open access differs from Open Source, which is a descriptor used for software with open code that is free to download, use, and modify.
To understand why this is important, watch this TedTalk by Erica Stone, titled Academic research is publicly funded - why isn’t it publicly available?.