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Operating Systems - David Vernon

Operating Systems - David Vernon

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The Need for <strong>Operating</strong> <strong>Systems</strong><br />

<strong>Operating</strong> System runs in ‘kernel’ mode<br />

– also called supervisor mode<br />

– it has full access to all the hardware<br />

devices<br />

Other system software and user<br />

applications run in ‘user’ mode<br />

– unable to access hardware devices directly<br />

Copyright © 2007 <strong>David</strong> <strong>Vernon</strong> (www.vernon.eu)

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