A journal available in electronic format (usually online).
The full-text of journal articles may be available in aggregated databases. However some publishers do not allow this, and others have pulled their contents in favor of their own online subscription products. The changing contents of subscription databases makes it a problem for libraries to catalog their serial holdings completely. In many cases the online catalog is therefore no longer a complete record of a library's electronic holdings, but instead an e-journals listing service or OpenURL vendor is used for this purpose.
Although many journals are still only available in print, there has been a slow trend towards publishing journals online. Several online journal formats dutifully replicate such as printed article components as page numbers, tables, graphs, and high-resolution images. Many journals now even accept submissions in electronic format, while some journals exist only electronically. Studies have indicated that (see Comparing Library and User Related Costs of Print and Electronic Journal Collections for example) electronic journals are worth the money when compared to print journals.
Besides the benefits of of electronic formats (such as the ability to reach simultaneous remote users online, for example), e-journals appear to be used and cited more frequently than their print counterparts. There is also no need for physical collection shelf space and storage, although this raises the problem that many electronic journals are only accessible via a vendor's subscription (they may even be bundled with unwanted titles), as opposed to print journals which are one-time purchases that are then owned by the library. The open access movement is built around alleviating these cost issues.