Man pages are written by sys-admin and developers for IT techs, and are intended more as a reference than as a how to. Man pages are very useful for people who are already familiar with Linux, Unix, and BSD operating systems. Use man pages when you just need to know the syntax for particular commands or configuration file, but they are not helpful for new Linux users. Man pages are not good for learning something new for the first time. Here are thirty best documentation sites on the web for learning Linux and Unix like operating systems.
Feeling lonely this holiday season? Try Xsnow. This little app will let is snow on the desktop. Santa and his reindeer will complete your festive season feeling with moving snowflakes on your desktop, with Santa Claus running all over the screen.
Linux comes with a host based firewall called Netfilter. According to the official project site:
netfilter is a set of hooks inside the Linux kernel that allows kernel modules to register callback functions with the network stack. A registered callback function is then called back for every packet that traverses the respective hook within the network stack.
This Linux based firewall is controlled by the program called iptables to handles filtering for IPv4, and ip6tables handles filtering for IPv6. I strongly recommend that you first read our quick tutorial that explains how to configure a host-based firewall called Netfilter (iptables) under CentOS / RHEL / Fedora / Redhat Enterprise Linux. This post list most common iptables solutions required by a new Linux user to secure his or her Linux operating system from intruders.
Unhide is a little handy forensic tool to find hidden processes and TCP/UDP ports by rootkits / LKMs or by another hidden technique. This tools works under both Linux / Unix, and MS-Windows operating systems. From the man page:
It detects hidden processes using three techniques:
- The proc technique consists of comparing /proc with the output of /bin/ps.
- The sys technique consists of comparing information gathered from /bin/ps with information gathered from system calls.
- The brute technique consists of bruteforcing the all process IDs. This technique is only available on Linux 2.6 kernels.
XPenguins is a program for animating cute cartoons animals in your root window. By default it will be penguins they drop in from the top of the screen, walk along the tops of your windows, up the side of your windows, levitate, skateboard, and do other similarly exciting things. Now you can send an army of cute little penguins to invade the screen of someone else on your network.
Tux Paint is a simple graphics educational painting programs for young children. It is free, Open Source software, distributed under the terms of the GNU General Public License. The program can be installed all all versions of Microsoft Windows, Apple OS X v10.3+, Linux, BeOS, Haiku, FreeBSD and NetBSD operating systems. It combines an easy-to-use interface, fun sound effects, and an encouraging cartoon mascot who guides children as they use the program.
One of the most common mistake is typing sl instead of ls command. I actually set an alias i.e. alias sl=ls; but then you may miss out the steam train with whistle.
