Productivity software

About Productivity Softwares

     

           Productivity software are those softwares that make computer useful. Productivity software is a category of application programs that help users produce things such as documents, databases, graphs, worksheets and presentations. 

        Many productivity applications are intended for business use. Examples of office productivity software include word processors, database management systems (DBMS), graphics software and spreadsheet applications. The definition of productivity software is sometimes broadened to include any type of application that is used to help people do their jobs, including collaboration and communication programs.
         Productivity software, like most types of applications, is increasingly available for mobile devices. However, mobile productivity apps are generally for basic tasks like e-mail, note-taking and calendar functions, rather than more substantial tasks, such as word processing.

WebBrowsers

Firefox 

       This program, headquartered at http://www.mozilla.org , is the most popular browser for Linux, and is also quite popular on Windows and Mac OS X. It’s a very complete browser, but it can consume a lot of memory, so it may not be the best choice on an older or weaker computer.

Galeon 

        This program, headquartered at http://galeon.sourceforge.net , is a browser that’s officially part of the GNOME Office suite. It’s designed as a lightweight GUI Web browser.

Konqueror

         This KDE program serves a dual function: It’s both a Web browser and a file manager. Konqueror does a good job with most Web pages. It’s fairly lightweight, and so is well worth trying, particularly if you use KDE.

Multimedia Apps

Audacity 

       This program, based at http://audacity.sourceforge.net , is an audio editor for Linux, similar to commercial products like Sound Forge for other platforms. You can use it to cut sections from an audio file, equalize volume, remove tape hiss or other noises, apply artificial audio effects, and more.

HandBrake  

       This program provides an easy way to convert between video formats, and particularly into formats that use the efficient H.264 encoding.

GIMP

        The GNU Image Manipulation Program (GIMP; http://www.gimp​.org ) is a still image manipulation program similar in broad strokes to Adobe Photoshop. (The GTK+ toolkit, which is the basis of GNOME and many other programs, was originally created for the GIMP.)

Linux Desktop Environments

About Desktop Environments

            Possibly, your first encounter with a Linux System could be desktop environment. A Desktop Environment is a set of programs that control the screen and provide small utility programs to perform tasks such as manage files. Moreover unlike Windows or MAC OS X, Linux provides multiple Desktop environment options, so if you don’t like one you can choose another.

Popular Desktop Environments

1) GNOME

GNOME is developed by The GNOME Project and provides the GNOME Desktop Environment, a graphical user interface and a set of core applications, and the GNOME Development Platform, a framework for building applications that integrate with the desktop.

Features:

• Completely open source
• Uses Metacity as default window manager
• Comes with Nautilus as default file manager
• Supports desktop notifications using a convenient messaging system
• Enables on/off switching of desktop notifications and many more

2) KDE

           The K Desktop Environment (KDE; http://www.kde.org ) is one of the

most popular desktop environments for Linux. It’s the default desktop environ-

ment for Mandriva and SUSE. It includes many powerful tools that integrate

together very well.

Features:

• Optional Menus
• Web Shortcuts. ...
• Accessibility Tools. ...
• K3B CD/DVD Ripper. ...
• Optional System Setting Displays. ...
• Rotating Icons and Widgets. ...
• Multiple Clipboard. ...
• Customizable Virtual Workspaces.

3) Or simply Roll your own

          It’s possible to build a desktop environment of your own from components you like. At a minimum, you need a window manager (dozens are available; see http://xwinman.org for a partial list), but for the configuration to truly be a desktop environment, you’ll need other components, such as a file manager and small productivity tools. All of the components need to be accessible from some sort of menu system.

Conclusion

   New users who are accustomed to Windows or Mac OS will probably be happiest with KDE; this environment is most like these traditional desktop operating systems’ environments. Although they deviate more from the model used by other OSs, GNOME and Unity aim for ease of use and so can be good choices for the inexperienced. Users who are familiar with commercial Unix OSs might give Xfce a try. Xfce and LXDE are good choices on systems that have less than copious RAM or less than blazing CPUs. People who like to customize everything or who have less-capable computers should investigate the roll-your-own approach.

Linux Boot Process

The Linux Boot process works as follows

Power on

BIOS (Basic Input Output System) is a software program comes pre-built in a motherboard chipset.
BIOS loads and scans for devices such as Hard Disk, CD-ROM, RAM, etc.
BIOS searches for MBR (Master Boot Record: 1st sector) of the primary hard drive, it scans for 1st stage loader (In our case boot loader is (GRUB LILO) and hands over the responsibility to MBR.
Boot PROM/FLASH/BIOS is proficient of loading the MBR into RAM and executing it.

MBR (Master Boot Record)

512 bytes of space –> MBR
MBR contains the information of loader of most operating system e.g UNIX, Linux and WINDOWS
MBR holds the small binary information of 1st stage of loader
MBR consist physical sector of the first disk drive (i.e 512 bytes) and it’s not part of any partition.
Placed on the prime disk drive, in the prime sector of the first cylinder of track is 0 and head is 0 (this whole path is generally booked for boot programs)
MBR involve a mini executable programs and a table specify the primary partitions.

Boot Loader

The boot loader termed from 1st stage loader and loads itself into RAM. All this go on in milliseconds.
The default stage 2 boot loader is a GRUB (Grand Unified Boot Loader) or LILO (Linux Loader)
Once GRUB is loaded into RAM, then it’s search for the location of Kernel.
GRUB will scrutinize the map file to find the kernel image, that is located under (/boot) and load it.
GRUB loads the kernel (vmlinuz-version) from /boot partition

Kernel

Mounts the root file system as specified in the “root=” in grub.conf
Kernel executes the /sbin/init program
Since init was the 1st program to be executed by Linux Kernel, it has the process id (PID) of 1. Do a ‘ps -ef | grep init’ and check the pid.
initrd stands for Initial RAM Disk.
initrd is used by kernel as temporary root file system until kernel is booted and the real root file system is mounted. It also contains necessary drivers compiled inside, which helps it to access the hard drive partitions, and other hardware.

Init

Init identifies the default initlevel from /etc/inittab and uses that to load all appropriate program.

Execute ‘grep initdefault /etc/inittab’ on your system to identify the default run level

If you want to get into trouble, you can set the default run level to 0 or 6. Since you know what 0 and 6 means, probably you might not do that.

Runlevel

When the Linux system is booting up, you might see various services getting started. For example, it might say “starting sendmail …. OK”. Those are the runlevel programs, executed from the run level directory as defined by your run level.

Under the /etc/rc.d/rc*.d/ directories, you would see programs that start with S and K.

Programs starts with S are used during startup. S for startup.

Programs starts with K are used during shutdown. K for kill.

Open Source Distributions

What is open source software?

Open source software is software with source code that anyone can inspect, modify, and enhance.
"Source code" is the part of software that most computer users don't ever see; it's the code computer programmers can manipulate to change how a piece of software—a "program" or "application"—works. Programmers who have access to a computer program's source code can improve that program by adding features to it or fixing parts that don't always work correctly.

Doesn't "open source" just mean something is free of charge?

No. This is a common misconception about what "open source" implies, and the concept's implications are not only economic.

Open source software programmers can charge money for the open source software they create or to which they contribute. But in some cases, because an open source license might require them to release their source code when they sell software to others, some programmers find that charging users money for software services and support (rather than for the software itself) is more lucrative. This way, their software remains free of charge, and they make money helping others install, use, and troubleshoot it.

While some open source software may be free of charge, skill in programming and troubleshooting open source software can be quite valuable. Many employers specifically seek to hire programmers with experience working on open source software

Why do people prefer using open source software?

People prefer open source software to proprietary software for a number of reasons, including:

Control. Many people prefer open source software because they have more control over that kind of software. They can examine the code to make sure it's not doing anything they don't want it to do, and they can change parts of it they don't like. Users who aren't programmers also benefit from open source software, because they can use this software for any purpose they wish—not merely the way someone else thinks they should.

Training. Other people like open source software because it helps them become better programmers. Because open source code is publicly accessible, students can easily study it as they learn to make better software. Students can also share their work with others, inviting comment and critique, as they develop their skills. When people discover mistakes in programs' source code, they can share those mistakes with others to help them avoid making those same mistakes themselves.

Security. Some people prefer open source software because they consider it more secure and stable than proprietary software. Because anyone can view and modify open source software, someone might spot and correct errors or omissions that a program's original authors might have missed. And because so many programmers can work on a piece of open source software without asking for permission from original authors, they can fix, update, and upgrade open source software more quickly than they can proprietary software.

Stability. Many users prefer open source software to proprietary software for important, long-term projects. Because programmers publicly distribute the source code for open source software, users relying on that software for critical tasks can be sure their tools won't disappear or fall into disrepair if their original creators stop working on them. Additionally, open source software tends to both incorporate and operate according to open standards.

Commercial Linux Distributions

Commercial Linux Distributions

Popular linux distributions

     Linux isn’t a complete operating system — it’s just a kernel. Linux distributions take the Linux kernel and combine it with other free software to create complete packages. There are many different Linux distributions out there.If you want to “install Linux,” you’ll need to choose a distribution. You could also use Linux From Scratch to compile and assemble your own Linux system from the ground up that is a lot of work to do.

     Though there are distributions available in market for free, setting up servers and maintaining them is not an easy job. You ought to have sound knowledge of operating system you are using and the underlying architecture. Moreover as Linux distributions are developed by community there is no one in particular who can be held responsible for fixing bugs or providing security patches. Here comes the commercial distributions into picture. These provide support, security patches as a service to the available open-source softwares.

Red Hat

Red Hat, Inc. is an American multinational software company providing open-source software products to the enterprise community. Founded in 1993, Red Hat has its corporate headquarters in Raleigh, North Carolina, with satellite offices worldwide.

Red Hat has become associated to a large extent with its enterprise operating system Red Hat Enterprise Linux and with the acquisition of open-source enterprise middleware vendor JBoss. Red Hat also offers Red Hat Virtualization (RHV), an enterprise virtualization product. Red Hat provides storage, operating system platforms, middleware, applications, management products, and support, training, and consulting services.

Red Hat creates, maintains, and contributes to many free software projects. It has acquired several proprietary software product codebases through corporate mergers and acquisitions and has released such software under open source licenses. As of March 2016, Red Hat is the second largest corporate contributor to the Linux kernel version 4.5 after Intel

SUSE

SUSE is built on top of the open source Linux kernel and is distributed with system and application software from other open source projects. SUSE Linux is of German origin, basically an acronym of “Software und System-Entwicklung” (software and systems development), and was mainly developed in Europe.