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Blu-ray Disc (BD) is a digital optical disc data storage format designed to supersedetheDVD format. The plastic disc is 120 mm in diameter and 1.2 mm thick, the same sizeasDVDs and CDs. Conventional (pre-BD-XL) Blu-ray Discs contain 25 GB per layer, with dual layerdiscs (50 GB) being the industry standard for feature-length video discs. Triple layer discs (100GB) and quadruple layers (128 GB) are available for BD-XL re-writer drives.[3]The name Blu-ray

Disc  refers to the blue laser  used to read the disc, which allows information to be stored at agreater density than is possible with the longer-wavelength red laser used for  DVDs. The majorapplication of Blu-ray Discs is as a medium for video material such as feature films. Besides thehardware specifications, Blu-ray Disc is associated with a set of multimedia formats. Generally,these formats allow for the video and audio to be stored with greater definition than on DVD.

The format was developed by the Blu-ray Disc Association, a group representing makers ofconsumer electronics, computer hardware, and motion pictures. Sony unveiled the first Blu-rayDisc prototypes in October 2000, and the first prototype player was released in April 2003 in Japan.

 Afterwards, it continued to be developed until its official release in June 2006. As of June 2008,more than 2,500 Blu-ray Disc titles were available in Australia and the United Kingdom, with 3,500in the United States and Canada.[4] In Japan, as of July 2010, more than 3,300 titles have beenreleased.[5] 

During the high definition optical disc format war , Blu-ray Disc competed with the HDDVDf ormat. Toshiba, the main company that supported HD DVD, conceded in February2008,[6] releasing its own Blu-ray Disc player in late 2009.[7] 

The Zip drive is a medium-capacity removable disk storage system that was introducedbyIomega in late 1994. Originally, Zip disks launched with capacities of 100 MB, but later versionsincreased this to first 250 MB and then 750 MB.

The format became the most popular of the super-floppy type products which filled a niche in the

late 1990s portable storage market. However it was never popular enough to replace the 3.5-inch floppy disk nor could ever match the storage size available on rewritable CDs andlater  rewritable DVDs. USB flash drives ultimately proved to be the better rewritable storagemedium among the general public due to the near-ubiquity of USB ports on personal computersand soon after because of the far greater storage sizes offered. Zip drives fell out of favor for massportable storage during the early 2000s. The Zip brand later covered internal and external CDwriters known as Zip-650 or Zip-CD, which had no relation to the Zip drive.

 A floppy disk, or diskette, is a disk storage medium composed of a disk of thin andflexiblemagnetic storage medium, sealed in a rectangular plastic carrier lined with fabric thatremoves dust particles. They are read and written by a floppy disk drive (FDD).

Floppy disks, initially as 8-inch (200 mm) media and later in 5.25-inch (133 mm) and 3.5-inch(90 mm) sizes, were a ubiquitous form of data storage and exchange from the mid-1970s well intothe first decade of the 21st century.[1] 

By 2010, computer motherboards were rarely manufactured with floppy drive support; 3 1  ⁄  2-inch

floppies could be used as an external USB drive, but 5 1  ⁄  4-inch, 8-inch, and non-standard drives

could only be handled by old equipment.

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While floppy disk drives still have some limited uses, especially with legacy industrial computerequipment, they have been superseded by data storage methods with much greater capacity, suchas USB flash drives, portable external hard disk drives, optical discs,memory cards, and computernetworks. 

 A magnetic stripe card is a type of card capable of  storing data by modifying themagnetism of tiny

iron-based magnetic particles on a band of magnetic material on the card. The magnetic stripe,sometimes called swipe card or magstripe, is read by swiping past a magnetic reading head. 

Magnetic recording on steel tape and wire was invented during World War II for recording audio. Inthe 1950s, magnetic recording of digital computer data on plastic tape coated with iron oxide wasinvented. In 1960 IBM used the magnetic tape idea to develop a reliable way of securing magneticstripes to plastic cards,[1] under a contract with the US government for a security system. A numberof  International Organization for Standardization standards,ISO/IEC 7810, ISO/IEC 7811, ISO/IEC7812, ISO/IEC 7813, ISO 8583, and ISO/IEC 4909, now define the physical properties of the card,including size, flexibility, location of the magstripe, magnetic characteristics, and data formats.They also provide the standards for financial cards, including the allocation of card number ranges

to different card issuing institutions.

Compact disc, or CD for short, is a digital optical disc data storage format. The format wasoriginally developed to store and play back sound recordings only (CD-DA), but was later adaptedfor storage of data (CD-ROM). Several other formats were further derived from these, includingwrite-once audio and data storage (CD-R), rewritable media (CD-RW), Video Compact Disc (VCD),Super Video Compact Disc (SVCD), Photo CD, PictureCD,CD-i, and Enhanced Music CD. AudioCDs and audio CD players have been commercially available since October 1982.

Standard CDs have a diameter of 120 millimetres (4.7 in) and can hold up to 80 minutes of

uncompressed audio or 700 MiB (actually about 703 MiB or 737 MB) of data. The Mini CDhasvarious diameters ranging from 60 to 80 millimetres (2.4 to 3.1 in); they are sometimes used for CDsingles, storing up to 24 minutes of audio or delivering device drivers. 

 At the time of the technology's introduction it had much greater capacity than computer harddrives common at the time. The reverse is now true, with hard drives far exceeding the capacity ofCDs.

In 2004, worldwide sales of CD audio, CD-ROM, and CD-R reached about 30 billion discs. By2007, 200 billion CDs had been sold worldwide.[1] Compact discs are increasingly being replacedor supplemented by other forms of digital distribution and storage, such as downloading and  flashdrives, with audio CD sales dropping nearly 50% from their peak in 2000.[2] 

DVD is a digital optical disc storage format, invented and developed by Philips, Sony,Toshiba, 

and Panasonic in 1995. DVDs offer higher storage capacity than compact discswhile having the

same dimensions 

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 A hard disk drive (HDD)[note 2] is a data storage device used for storing andretrievingdigital information using rapidly rotating disks (platters) coated with magnetic material. AnHDD retains its data even when powered off. Data is read in a random-access manner, meaningindividual blocks of data can be stored or retrieved in any order rather thansequentially. An HDDconsists of one or more rigid ("hard") rapidly rotating disks (platters) with magnetic heads arrangedon a moving actuator  arm to read and write data to the surfaces.

Introduced by IBM in 1956,[2] HDDs became the dominant secondary storage device for generalpurpose computers by the early 1960s. Continuously improved, HDDs have maintained thisposition into the modern era of  servers and personal computers. More than 200 companies haveproduced HDD units, though most current units are manufacturedbySeagate, Toshiba and Western Digital. Worldwide revenues for HDD shipments are expected toreach $33 billion in 2013, a decrease of approximately 12% from $37.8 billion in 2012.

The primary characteristics of an HDD are its capacity and performance. Capacity is specifiedin unit prefixes corresponding to powers of 1000: a 1-terabyte (TB) drive has a capacity of1,000 gigabytes (GB; where 1 gigabyte = 1 billion bytes). Typically, some of an HDD's capacity isunavailable to the user because it is used by the file system and the computer  operating system, and possibly inbuilt redundancy for  error correction and recovery. Performance is specified by the

time to move the heads to a file (Average Access Time) plus the time it takes for the file to moveunder its head (average latency, a function of the physical rotational speed in revolutions perminute) and the speed at which the file is transmitted (data rate).

The two most common form factors for modern HDDs are 3.5-inch in desktop computers and 2.5-inch in laptops. HDDs are connected to systems by standard interface cables such asSATA (Serial

 ATA), USB or SAS (Serial attached SCSI) cables.

 As of 2012, the primary competing technology for secondary storage is flash memory in the formof  solid-state drives (SSDs). HDDs are expected to remain the dominant medium for secondarystorage due to predicted continuing advantages in recording capacity and price per unit ofstorage;[3][4] but SSDs are replacing HDDs where speed, power consumption and durability aremore important considerations than price and capacity.[5][6] 

 A USB flash drive is a data storage device that includes flash memory with an integratedUniversalSerial Bus (USB) interface. USB flash drives are typically removable and rewritable, and physicallymuch smaller than an optical disc. Most weigh less than 30 grams (1.1 oz).[1]  As of January 2013,drives of up to 512 gigabytes (GB) are available.[2]  A one-terabyte (TB) drive was unveiled at the2013 Consumer Electronics Show and will be available during 2013.[3] Storage capacities as largeas 2 TB are planned, with steady improvements in size and price per capacity expected.[4] Someallow up to 100,000 write/erase cycles, depending on the exact type of memory chip used, and a

10-year  shelf storage time.[5][6][7] 

USB flash drives are often used for the same purposes for which  floppy disks or  CD-ROMswereused, i.e., for storage, back-up and transfer of computer files. They are smaller, faster, havethousands of times more capacity, and are more durable and reliable because they haveno moving parts. Until about 2005, most desktop and laptop computers were supplied with floppydisk drives in addition to USB ports, but floppy disk drives have been abandoned due to their lowercapacity compared to USB flash drives.

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USB flash drives use the USB mass storage standard, supported natively by modernoperatingsystems such as Linux, OS X, Windows, and other  Unix-like systems, as well as many BIOS bootROMs. USB drives with USB 2.0 support can store more data and transfer faster than muchlarger  optical disc drives like CD-RW or DVD-RW drives and can be read by many other systemssuch as the Xbox 360, PlayStation 3, DVD players and in a number of handheld devices such assmartphones and tablet computers.

 A flash drive consists of a small printed circuit board carrying the circuit elements and a USBconnector, insulated electrically and protected inside a plastic, metal, or rubberized case which canbe carried in a pocket or on a key chain, for example. The USB connector may be protected by aremovable cap or by retracting into the body of the drive, although it is not likely to be damaged ifunprotected. Most flash drives use a standard type-A USB connection allowing connection with aport on a personal computer, but drives for other interfaces also exist.

USB flash drives draw power from the computer via the USB connection. Some devices combinethe functionality of a digital audio player  with USB flash storage; they require a battery only whenused to play music.

Disadvantages of CCE System 

• It's main Disadvantages is that "grading system" because for example students that score

 between 90 and 100 will get an A* grade. Who is scoring 90 marks and 99 marksrespectively will still both attain an A* No one can Judge who is deserve 90 who is deserve

100.• Students will take studies casually and secondary. 

• Major problem a percentile mark has been introduced by the board. • Assistment and other co curriculum activities is too much time consuming and expensive

assignments and projects.

• Student are busy completes lots of project work, they haven't sufficient reading time. CCE initiate by regularly assessment of a student all over not at the end of any term.

Comprehensive means takes all round development of a child's personality. Evaluationcan understand by a child will be assessed not only in terms of his knowledge about a

subject but his participation in other activities also.It is a systematic determination ofa subject's merit, worth and significance, using criteria governed by a set of standards

it can assist an organization to assess any aim, realizable concept or proposal, or any

alternative, to help in decision-making.By these system student become moreactive.If any student do not wish CBSE exam in Class X by the Board, he/she can join

schools and institutions affiliated to any Boards. He/she can carried out by the school

exam. Students shall following School base internal assessment. CBSE also providesfacility that question papers & marking system prepared by the CBSE Board. After thatthe CBSE will collect mark sheets and grades from institution/schools, then classes IX

and X for assessments of all Scholastic as well as Co-scholastic areas for whicharrangements are being made. students measures, by testing and feedback given by

teachers.Some Good and identifiable features of CCE are academic year divided into two termsAcademic year divided into two terms. First term is starts with April to September andsecond term is starts with October to March. According to CCE System student

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performs various school based assessments. In this system student's score grades

which will be depend on his/her assignments, extra curricular activities. The gradingsystem is-

A1 is for 9.1-10.0, A2 is for 8.1-9.0, B1 is for 7.1-8.0, B2 is for 6.1-7.0, C1 is for5.1-6.0, C2 is for 4.1-5.0, D is for 3.1-4.0,

E1 is for 2.1-3.0, E2 is for1.1-2.0.

Why we Need CCE System in India According to department of education CCE helps reducing stress of student .By these

system student can develop their aptitude as well as academic performance. These

system aim is all over development of student's personality. Due to globalizationdepartment of education focus on development of all over personality and skill.

Reduce the workload on students and improve his/her over all skills.

Advantages of CCE System 

• The Main advantage of CCE system is reduce stress on. Student can complete

project or Formative and Summative Assessment .

• The CCE system also focuses on develop student's personality which helps studentidentify in global. He can take decisions what is wrong and what is right.• By these CCE System there are no pressure for students to become highly academic

because they aim to encourage individuals to choose subjects based on their interestswhile retaining the importance of academia. They aim to make the students feel more

relaxed so they improve on their academic ability without feeling under pressure. 

 A solid-state drive (SSD) (also known as a solid-state disk [1][2][3] or electronic disk,[4]though itcontains no actual "disk" of any kind, nor motors to "drive" the disks) is a  data storage

device using integrated circuit assemblies as memory to store data persistently. SSD technologyuses electronic interfaces compatible with traditional block input/output (I/O) hard disk drives, thuspermitting simple replacement in common applications.[5]  Also, new I/O interfaces like SATAExpress are created to keep up with speed advancements in SSD technology.

SSDs have no moving mechanical components. This distinguishes them fromtraditionalelectromechanical magnetic disks such as hard disk drives (HDDs) or  floppy disks, whichcontain spinning disks and movable read/write heads.[6] Compared with electromechanical disks,SSDs are typically more resistant to physical shock, run more quietly, have lower access time, andless latency.[7] However, while the price of SSDs has continued to decline in 2012,[8] SSDs are stillabout 7 to 8 times more expensive per unit of storage than HDDs.

 As of 2010, most SSDs use NAND-based flash memory, which retains data without power . Forapplications requiring fast access, but not necessarily data persistence after power loss, SSDs maybe constructed from random-access memory (RAM). Such devices may employ separate powersources, such as batteries, to maintain data after power loss.[5] 

Hybrid drives or solid state hybrid drives (SSHD)[9][10] combine the features of SSDs and HDDs inthe same unit, containing a large hard disk drive and an SSD cache to improve performance offrequently accessed data. These devices may offer near-SSD performance for many applications.

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