Unix Operating Systems Information Document

Hi all,

I prepared a document on UNIX OS. Its an humble attempt to share my knowledge.

Please review the document attached and correct if any mistakes and any suggestions to make it more useful and any troubleshooting information if needed to add.

Please help in making the document to add more information

Windows is a collection of OS's and you can't really lump them together. XP has the NTFS filesystem which has rather powerful file permission capabilities. You can use a FAT filesystem with XP but Microsoft recommends ntfs. In my mind the glaring difference between Windows/Unix is that Unix is multi-user. Diff number 2 would be the XP GUI shell (explorer). Internally, unix has a monolithic kernel while XP has a microkernel (more or less). (Linux is also monolithic and this was the subject of a flamewar between Tovalds and Tennenbaum. Please remember our rules and do not start a flame war here. The thread will be quickly closed should that happen.) And a final large difference is the windows registry concept.

Your diagram does not strike me as correct. The shell should be a layer unto itself.

Swapping is moving entire processes into core or back to the swap area. At first Unix could swap but had no paging. After CPU's had MMU's paging became possible. Now unix pages all the the time and rarely swaps as a last resort. Some OS's (and I am thinking of HP-UX in particular) no longer swap at all. This leaves that swap area with a poor name! (Encrypted passwords have been removed from the password file too. Users rarely have home directories in /usr anymore. Unix has evolved a lot...)

The best thing you could do to make it more useful is to put it into a format that can be read by everyone, e.g., HTML.