Memory

                                                       MEMORY

A memory is just like a human brain . Memory is the most important part of computer system , that holds programs as well as data storage capacity of computer is called memory . 

        Normally we classify the information to be stored into two basic categories : Data and instructions.

   HISTORY OF MEMORY

1. 1890:Punch Card = Punch Card predate electrical computers. A punch card was a thick sheet of paper with holes punched through it in patterns that could then be interpreted.

2. 1932:Magnetic drum memory = It was invented in the 1930 in Austria by Gustav Tauschek , and widely used in the 1950s and 1960s as the main working memory of computers . It capacity was about 10KB .

3. 1950: Paper tape = the tradition of punch cards , paper tape consisted of a long strip of paper where holes were punched at various location to represent the data .

4. 1950: Magnetic tape = It is the same manner to paper but was able to store more information . It was stored in a roll and read /write . It's great for archiving because of its high capacity, low cost and long durability.

5. 1956: IBM's First hard drive = It had 50,24-inch discs with total storage capacity 5 MB.

6. 1963: Cassette tape = The first compact audio cassette was introduced by Philips .

                                                                                    The compact cassette was also a popular way of data storage for personal computers in the late 70s and 80s . It's storage capacity about 660KB per side on a 90-minute tape.

7. 1971:Floppy disk = The disks used with a floppy disk drive are small removable disks made up of plastic coated with  magnetic recording material . Floppy can be accessed from both the sides of the disk. A floppy is about 0.64 mm thick and is available in diameters 5.25 inch and 3.5 inch.

8. 1982: CD-ROM = A CD-ROM is a non-erasable disk used for storing computer data . The standard uses 12cm disk and can hold more than 650 MB .

9.  1995 DVD = A DVD ROM is used for providing digitized compressed representation  of video as well as the large volume of digital data . Both 8 and 12 cm diameters are used with a double sided capacity of up to 17GB . The first DVDs were available in Japan .     

10. 1999 SD memory cards = A security digital card is one which is going to store additional amounts of  information . It's used for mobile devices such as cameras and smart phones.

11. 2000 USB Flash drive = A USB flash drive is data storage device that includes flash memory with an integrated USB interface . compared with floppy  disks or CDs , they are smaller and faster .

12. 2006 Cloud storage = Cloud storage is a cloud computing model that stores data on the internet .