Why is linux not affected by virus, is it completely safe from malwares?

Why is de-fragmentation not needed in linux?

Please elaborate me the answers.

Hello,

Read this page at www.tuxradar.com, it'll provide an answer to a lot of your questions. The Security sections explains in easy terms what you're asking about viruses.

Kind regards,

Eric

On defrag:

http://geekblog.oneandoneis2.org/ind..._defragmenting

Google is your friend for this type of question and will result in more goodwill from your fellow Linux users. The link I got, which is reputable and #1 on Google search from the query "defragmentation linux", is appropriate to your question.

The Linux background is Unix, a secure multi user system.
Lots of normal file systems available, file systems with
almost no fragmentation. Linux can run on anything.
The most of the internet ( and Google ) runs on Linux.
Super computers use Linux.
And Linux has excellent memory management.

The windows background is a more primitive OS, single user.
Originally meant for 16 bit 8088 ? Later: Intel 386.
The file systems still do fragmentation, thus they need
periodically de-fragmentation done.
And windows still has poor memory management. It cannot
take advantage of all RAM "all the time", like Linux can.
They could have improved both issues. They didn't .....
( Rumors a year ago said no defrag, windows 7 ? )
..

I think the specific difference in ram use you are referring to does not actually exist.

Windows lies about memory statistics.

As you probably know, Linux memory reporting tools give correct simple values for memory statistics even though the underlying reality is too complex to be represented by those simple values. The result is many users know they are confused and/or think something is broken.

Windows memory reporting tools intentionally give incorrect simple values to prevent the user from realizing that he can't actually get a meaningful measure of memory use and to stop users from thinking something is broken.

Hi,

'Linux File System' section of 'Slackware-Links'. More than just Slackware® links! Should help you to understand by looking at the subsection: 'Understanding UNIX/Linux file system'. Look at the other referenced links to gain more information to aid you to understanding.