SAR

The SAR, or specific absorption rate, of a mobile phone is the amount of RF energy it exposes its user to. In the United States, mobile phones need to have a SAR rating of 1.6 watts per kilogram (W/kg) or less. In Europe, the limit is 2 W/kg. While there have been plenty of studies that conclude that phone based RF radiation is harmful, there are an equal amount that find the opposite to be true. In any event, a device with a lower SAR rating will pose less of a risk than one with a higher rating.

S90

S90, previously known as Series 90, is the software platform that Nokia runs on top of the Symbian OS in its 77xx series of touchscreen enabled multimedia devices. Nokia has announced that S90's functionality will likely be folded into the S60 platform, and that S90 will cease to be developed.

SMTP

SMTP is short for Simple Mail Transfer Protocol, an application protocol used to send mail from one user to another. it is the standard for email transmission used on the Internet. SMTP does not provide a method for an end user to read email, rather it simply makes sure that the mail gets to the user's home mail server.

S40

S40 is the platform that Nokia runs on its feature phone handset models. Unlike S60, it does not run on top of the Symbian OS, but rather runs on a fully proprietary system. Formerly known as Series 40, the system generally only allows the user to install Java based applications instead of the native applications that can be installed by users of S60 devices.

S80

S80, previously known as Series 80, is the software platform that Nokia runs on top of the Symbian OS for its 9000 series of communicator devices. Nokia has announced that S80's functionality will be folded into the S60 platform, and that S80 will cease to be developed.

Symbian

Symbian Ltd is the software firm that develops and licenses the Symbian OS. Originally spun off from Psion, a maker of PDA devices, the company now focuses on its operating system products. The company is jointly owned by Nokia, Ericsson, Matsushita (AKA Panasonic), Siemens, Sony Ericsson, and Samsung. Motorola was previously a shareholder, but it sold its shares to Psion and Nokia. Nokia later acquired Psion's shares and is now the largest shareholder in the company.