iTunes is a PMP application, utilized for playing and organizing your music and videos. This software is also a program that allows the user to handle the music on iPhones and iPods. Furthermore, this software can connect to the iTunes Store using the Internet to let you buy and download music, videos, TV programs, applications, games for iPods, audio books, podcasts and also, ring tones. It is using to download software for iPhones and iPods that are using the iPhone OS X.

iTunes was released by Apple Inc. on January 9, 2001, to the Macworld Expo, an annual conference kept in  San Francisco. The most recent version of iTunes, the iTunes 9, was released at Apple's September 2009 "Rock and Roll" event.

iTunes is accessible and ready for use and download for free for Mac OS X v10.4+, Windows 7, Windows XP and Windows Vista from Apple's official site. It is also sold together with  all Macintosh computers, and also with some HP and some Dell computers. Elder variants are available for Mac OS 9, Mac OS X v10.0 to 10.3, and for Windows 2000.

iTunes keeps the management  of  the tracks by producing a virtual library storage, permitting that users to be able to access and change a song's assigns. These attributes, named also  metadata, are kept in 2 different library registers.

The 1^st is a binary file named iTunes Library and it have a copyrighted file format that it is shorted as ITL. It gets datas like artist or genre from the files format's tag capacities , like the ID3 tag, and depots iTunes typically informations like  how many times was played or the rating numbers. iTunes in a typical manner  reads library data only from this files.

The 2^nd file, iTunes Music Library. xml, is reviewed every time the information in iTunes is modified. It purposes an XML format, letting program coders to easily write software that can access the library datas (as play count, last played date, and rating, that are not standard domains in the ID3v2.3 format). Apple's own iDVD, iMovie, and iPhoto programs access also this second library.

If the 1^st file is corrupted, iTunes will try  to remake  it from the XML file. Detailed 3^rd party instructions  concerning  this are documented in another place. There have been some fears, sustained by Mark Pilgrim, who told that this feature will produce an "undocumented binary black hole" for the reason that  the recovery from the XML file may not act properly.

It has also been said that this program does not automatically chase to change into actual datas in the library. If the user will move or erase a file, iTunes will display an exclamation mark near the library introduction and the user will need to amend the library record all by himself. Some 3^rd party implemented programs resolve this problem.

iTunes it is used also for ripping the CDs, but it can't rip any DVDs. Even so, in 2008, Apple released iTunes Digital Copy, a program that can do this, as  a bonus attribute  on some DVDs that allows a copy-protected. Like with any other digital music management tool, users have to use a digital converter to import analog recordings, like vinyls or audio cassettes to their iTunes library.

A personal iTunes Library can be shared trough a local area network using the closed, copyrighted DAAP, name that comes from the shorten of Digital Audio Access Protocol, released by Apple for this role. DAAP depends on the Bonjour network service using Frame Work, an Apple provided software. The DAAP specifications aren't available for the general users, but  some 3^rd part programmers knows them. An example can be the privately held consumer electronics firm specialized in home digital media products, Roku. Also, the software has been changed and is now used to share play lists from  softwares that don't have the Apple's signature. DAAP permit shared lists of songs between the similar subnets to be automatically recognized. When a song is distributed, iTunes can play the song but won't save it on the local storage device, with the objective of preventing unauthorized copies. Tracks with the AAC format can also be accessed, but the user will need to complete an authentication form. A largest number of users that may connect to another single user in twenty four hours is five. The View options are usually available to iTunes users but the Cover Flow option isn't available when playing a shared library through a network.

The iMac is a line of Macintosh desktop computers released by Apple Inc. The current Apple iMac provides either an Intel Core 2 Duo, Intel Core i5, or Intel Core i7 CPU, nVidia GeForce 9400M integrated graphic card or an ATI Radeon HD 4670 with options to update to the ATI Radeon HD, available for the 27 inches model only, and an alternative of glossy 21.5" or a 27" LCD displays.

In early February 2006, Apple affirmed reports of video display troubles on the new Intel based iMacs. At the replaying of a video on Apple's Front Row browser, some 20 inches iMacs proved random horizontal lines, ghosting, video tearing and other bugs. The problem was solved with a software upgrade.

In late 2006, Apple released a new version of the iMac which included a Core 2 Duo chip and a cheaper price. Apple added a new 24 inches model with a resolution of 1920 x 1200, WUXGA, making it the first iMac that was capable to display 1080 pixels content at a full resolution, and a VESA Flat Display Mounting Interface. Except for the 17 inches 1.83 GHz CPU model, this version also had an 802.11n draft card.

While the elder  iMac models had a white polycarbonate case, same  as iMac G5, this generation has a case shaped like Apple's Cinema Displays but as  styling as the iPhone. In addition, the iMac line is now produced using the same unibody structure as the MacBook Pro. Former aluminium iMac models had a black back made from plastic, but the actual model has an aluminium back extended with the front aluminum plate.

In March of 2009, Apple released a some minor brush up of the iMac class. Changes enclosed a fourth USB port, the removal of the Fire Wire 400 port, leaving only the FireWire 800 port, and a bit redesigned case. The outside design was nearly identical to the elder Intel-based iMacs. This line contains  a  20 inches configuration and three 24 inches configurations, instead of 2 at each monitor size as the previous. Apple Inc. doubled the usual RAM and hard disk capacity on all models, moving the memory to the DDR3 specification. This changes also brought in a new littler and more succinct Apple Keyboard in a QWERTY system that excluded the num keypads.



In October of 2009, a 16:9 aspect ratio display was introduced in 21.5 inches and 27 inches models, taking the place of the 20 inches and 24 inches screens of the elder generation. Video card options completely changed to ATI, save for the classic onboard nVidia card in the base model. The iMac's CPU selection attended a major increase. Existing Core 2 Duo technology provided higher speed on the lower models, and Intel's new Core i5 and Core i7 chips are now accessible in the higher end models, representing the 1st quad-core iMac. Default RAM memory has as well been increased all over the iMac line. With the produce and the release  of the larger displays, Apple doubled the number of memory slots from 2 to 4. Accordingly, the maximum memory capacity was also doubled up to 16GB. The current iMac comes with the wireless Apple Magic Mouse, wireless Apple Keyboard, Bluetooth v 2.0 and AirPort cards, an internal iSight camera, and a power electric cord.

The available processors are at 2.66GHz, 2.93GHz, or 3.06GHz Intel Core 2 Duo processor with 6 MB shared L2 cache memory at full processor speed and 1066 MHz front side bus, Replaced by Intel Direct Media Interface 2.5GT/s available for high-end 27" only.

The video card can be, optional, found as nVidia GeForce 9400M with 256MB shared with main memory for the low-end 21.5" only, or ATI Radeon HD 4670 with 256MB of GDDR3 SDRAM or ATI Radeon HD 4850 with 512MB of GDDR3 SDRAM for 27 inches only.



Wireless-N functionality demands the AirPort Extreme Wireless-N Router, which comprises wireless-N enabler software to be installed on user's iMac. In place of this, the enabler software may be buy from Apple separately. The optical drive speeds are the maximum possible for every drive.

In 2008, a lawsuit action was registered against Apple Inc. in San Jose by Kabateck Brown Kellner, LLP, demanding that Apple is betraying consumers by claiming that both the 20 inches and 24 inches iMac are able of displaying hundreds of colors at all resolutions, when the 20 inch models are only able to display 262,144 colors. The 20 inches screens use 6 bit twisted film (TN) LCD display, which the complainant claims that it is the "least expensive of its type," sporting a not that wider viewing angle than the display of the 24 inches model, lower color depth, lower color accuracy and greater susceptibleness to wash out.

The iPhone operating system, known as OS X iPhone is developed by Apple Inc. specially for this type of phones, used also on the iPod Touch.  Just like the Mac OS X does, this operating system uses the Darwin foundation, which is compose by code derived from Next Step, BSD and some other free software projects. That's why, every iPhone and iPod Touch is compatible with the Single UNIX Specifications version three and Posix UNIX applications and utilities. It takes less than 240 MB of the device's memory storage and it is based on the concept of direct manipulations.

A home screen, rendered by Spring Board, with application images, and a platform at the lower side of the screen, indicating the icons for the applications the user access more often, is presented when the phone is turned on or anytime the home button is pushed. The display has a status bar to the opposite side of the top to display data, like time, battery level, signal intensity. The rest of the display is consecrated to the used  application. There is no concept of opening or closing  applications, only starting an application from the home display, and leaving the application to return back. It is possible to force-out an application to quit by pressing the power button until the "slide to power off" button appears, and then pressing the home button down. Although some multi-tasking is permitted it is not noticeable . However, it is restriction to applications released only by Apple. Third-party applications are ended when left, but with the 3.0 software upgrade, notices will be able to be downloaded from Apple's sites to the iPhone or iPod Touch. Many another of the admitted applications were created to work together, making the possibility of the sharing or cross extension of data from one to another. For example, a number  of phone can be selected  into an application and saved as a contact into another or dialed.



On October 17, 2007, into an announce posted to Apple's Hot News, Steve Jobs said that a software development kit, also known as SDK, would be released for3rd part programmers . The SDK was published on March 6, 2008, and let the developers to create  applications for the iPhone OS X, and also  test them in a simulator, which looks exactly like the iPhone. Still, loading an application into the simulator is accepted only  after  you pay a fee for the iPhone Developer Program.

Programmers  are permitted to set any cost for their software and release them for distribution on the Apple Store, of which they will get a 70% pay. Alternate, they may choose to release the apps as free sources and don't need to pay any other cost.



Since it was released, there has been some disputes involving the refund policy in the published print of the developer agreement with Apple Inc. In accord with the idea that programmers must agree to, if someone buys an app from the app store, 30% of the cost goes to Apple, and 70% to the coder. If a refund is gave back to the buyer, only if Apple agrees, the 30% is returned to the buyer from Apple, and 70% from the programmer. Apple Inc. can get another 30% of the cost from the programmer to cover their loss.

Apple didn't announced any projects to enable Java to work on the iPhone. Sun Microsystems announced that they will  release a Java Virtual Machine, known as JVM for iPhone operating system, founded on the Java Platform, Micro Edition. This will help the  Java programs to run on iPhone and iPod Touch.

Right after this announcement, programmers which were familiar with the SDK's terms of agreement thought that by not allowing third-party programs  to run in the background, like to be able to answer if your phone calls and the application to still work, letting  a program to download the code from another program, or allowing an application to interact with a third-party application, like JVM  with Safari, could block the development of the JVM without the Apple's pattern.



It is more than sure that Java running on the iPhone is beyond the boundary  of the iPhone SDK Agreement.

The iPhone OS don't support Adobe Flash, and Flash movies can't be viewed on web pages. Even thought Adobe released 2 versions of this software, Apple views  incomplete and not as suitable for the iPhone. Apple's argumentation to the public so far has been that Flash would be too difficult to handle or use especially because of size or weight for the iPhone, while Flash Lite, the second version released, would not allow a suitable feel for users.

The iPhone is an multimedia and internet enabled smart phone released by Apple Inc. It have some common features between every model like video camera phone, portable media player (PMP), an internet client with web browsing, e-mail and wi-fi. Also it have a multi touch display which renders a virtual keyboard in a QWERTY system  as an alternative to the physical keyboard.

The iPhone 3G have a smoothie metal case with a black bare on the bottom. The front has a bezel made from shiny metal that ends around the display. The keypads are constructed from plastic and very easily to move. The headphone has a black plastic black and a mesh made from plastic which is hiding the speakers in front.



The 3G iPhone has a glass finish, available in black and white. This coating runs unbreakable around the phone, and ends in the same spot with the metal bezel. The keypads of iPhone 3G are made from metal, a shiny one, with the exception of home button. This gives them a more thinker feel at their touch, despite the old 2G model which had plastic buttons. Instead of the classic black case of the earphones from 2G model, the 3G model have a silver mesh, perforated. The same model of mesh is used also for the bottom speaker phone.

A difference between 2G and 3G aspect it is the 2 screws from the bottom side of the second one, which can be used for opening the case. Another big difference can be the new  headphone jack., but the main difference at the exterior between them is the case from the back side, 3G model being more shaped than the other one. The 2G model is rounded and shaped on the edges but flat on the backside. The 3G model  the shapes are more pronounced and the phone is also wider than the original model. The display of the iPhone 3G is also a bit more warmer than the original model.

The upgrade from 2G to 3G didn't make very many differences between integrated features. The 3G have GPS, and the capability to download files at a high speed, more higher than 2G. The GPS is very accurate , needing only few seconds to  discover a location. Comparing to the iPhone 2G and the original iPhone, the new model it is distinctly more precise and a lot more faster. While the 3G show less bars, the 2G smart phone  full bars. You can make a simple test and try to download some software from Apple Store or browse the internet. The page update rate is bigger on the 3G version than on the other model.

Except this GPS and the 3G network, there isn't any major difference between this two models of Apple's smart phones or any other features.



Comparing the both models, you can see a huge difference between the hardware part, the software being mostly the same.

As operating system, both 3G and the Original use the iPhone OS 3.1.2, build as 7D11 and released in October 8, 2009. Both have the same battery of 3.7 V differing the number of ampere for hour, the 1^st one having 1150 and the second a little more, around 1400. Both using a lithium ion polymer battery which it is internal rechargeable and not able to be removed.

As for processors there aren't any differences neither here. The original 2G and the 3G iPhones have a Samsung 32 bit RISC ARM1178JZ v1.0. with 620 MHz that can be under clocked to 412 MHz  and a Power VR chipset from the MBX Lite 3D category. If the original had 3 variants of flash memory capacity to choose, the 3G model it is available only in 8 GB and 16 GB types, because they considered the 4 GB type a little more insufficient and useless.



Both iPhones have the same memory of 128 MB DRAM and the same display with 320 x 480 pixels, 3,5 inches, 2:3 aspect ratio, and 18 bit which provides 262 144 colors, all integrated into a LCD with 163 pixels per inch (ppi).

The input layout is made by the multi touching screen, the headset controls, the 2 proximity and ambient light sensors and the 3-axis accelerometer. Also, the camera have 2.0 mega pixels with geo tagging.

Excepting the Wi-fi band, the Bluetooth 2.0, the USB 2.0 and the quad band GSM, 3G also included for connectivity the A-GPS, a tri band UMTS/HSDPA.

iMac is a ranged all-in- one desktop computers made by Apple Inc. under the Macintosh line. It has been the prime part of Apple's desktop proposal since its released in 1998, and has pass through 4 distinct forms. The original one, the iMac G3, was shaped and had a CRT monitor, enclosed by translucent plastic. The 2^nd major upgrade, the iMac G4, had a hemispherical  base design with a LCD monitor and all the main components. The Intel iMac and the iMac G5 placed all the hardware components behind the monitor, creating a short and thick unified design that angles up and down on a metal base. The last iMac have the same shape as the previous, but is a little more thinner and made from aluminum and black bordered glass for the case.

iMac received a lot of considerable critical attitudes, including express approval of Walt Mossemberg, an american journalist who works like the principal columnist for the Wall Street Journal and who named it the "Gold standard of desktop computers". CNET said about the first 24 inches Core 2 Duo that it's a "must-have desktop" and the Forbes Magazine about the original colored line that it is an "industry altering success".

On the start of the 2009, in March, Apple upgraded iMacs with new Nvidia chipsets a new keyboard without numeric pad keys and a new Mini Display Port.

On October 20, 2009, Apple added to iMac two new LED backlit 16:9 widescreen at 21,5" and 27", instead of the old 20" and 24" which had a 16:10 aspect ratio. Also the hard drive and memory capacity increased and 2 new Core chips, i5 and i7 was added, starting a new era of iMac quad cores.

The dimensions of the display varied from generation to generation. So if the iMac G3 had a 15 inches CRT, the Aluminum iMac it is available in 4 types of LCD, of 20", 21,5", 24" or 27", despite the Intel Plastic IMac model that was available only in 3 variants of 17, 20 or 24 inches, also LCD.



The capacity of the hard drive varied also with every major upgrade. If at the start the iMac was available in 2 options of 4 and 60 gigabytes, now, the aluminium model can be bought with 250 GB or 2 Terabytes.

The Mac Operating system used, also have been upgraded year by year, now, the ultimate version been Mac OS X 10.6 .

In October, 2009, Apple Inc. released a  long expected refresh of iMac line. The 27" model have a digital video input port for a better allowing of the system to hold as a screen for other devices. Video card  was changed into ATI and the processor have been significant upgraded to Core 2 Duo.  The high end model have also implemented Core i5 and Core i7 chip sets, allowing the new iMac to be named as quad core for the first time. The default RAM  has been increased and the memory slots have been doubled, the maximum memory capacity also was doubled to 16 GB.

Dan Frakes from MacWorld advises that if they will keep iMac occupying the mid-range of Apple Inc.'s product line, Apple have nothing else to offer to the users which want some ability to expand or upgrade their personal computers but can't afford or just don't need a Mac Pro.



A new upgrade to the iMac was a removable mobile PCI express Module (MXM) as an interconnect standard for graphic modules.

The prime model of iMac was the first released Macintosh that included an USB port, but being the only interface for peripheral built -in it.  The unexpected success and popularity of this product helped the introduction of this interface among all the computer's industry.

Via this USB port, hardware producers could make some products that are able and compatible to work with both PCs and iMacs. Before this, Macintosh users had to look for a certain hardware, like mice and keyboards, special oriented and made for Mac's unique interface. Only two or three models of peripherals from specified manufacturers were made for this interfaces, and often was pretty expensive. Through the introduction of USB, the iMac users have been allowed to acquire a large collection of more cheaper devices and gadgets, like hubs, storage devices, scanners, keyboards, mice and USB flash drives. But as USB was pretty slower than a number of other type of ports available at that time like SCSI, iBooks and iMacs were pretty badly deprived in their efficiency until adequate replacements was released, such as Fire Wire or USB 2.