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RAM	Random Accessed Memory - simply put, memory which stores work in progress. RAM does not store data permanently, so information required to be kept must be saved in another format.
Readership	The number of people who actually read a publication. Often this is greater than the circulation as more than one person can read a document.
Response rate	The number of responses to a direct mail, email marketing or similar campaign calculated as a percentage of the total number of communications sent out.
RGB	The RGB system is used to display colour on computer monitors by mixing Red, Green and Blue to create millions of different colours. This is different to the CMYK system used in printing.
ROI	Return on Investment - the payback organisations receive as a result of improved efficiency, lower costs etc as a result of investing in specific computer systems.
ROM	Read Only Memory - memory that remains available at all times and is usually used to enable a computer to access and run its operating system.
Router	Hardware or software on a computer network that examines the address to which data is being sent and decides by which route it should be transmitted to its destination. A network administrator can often set priorities so that routers select either the fastest, cheapest or most direct routes as required. The most common routers are those enabling a computer to connect to the internet.
RSS	Really Simple Syndication enables easy distribution of web site or weblog content in a standard format based on XML. Many news and media organisations distribute their content via RSS feeds which can be read using a RSS feed reader or news aggregator software for desktop or laptop computers and mobile phones and other devices.