How data storage and retrieval has changed overtime

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Data Storage

Data storage is a term used for archiving data in electromagnetic or other forms for use by a computer or device computing environment

There are different forms of data storage such as physical and remote

Storage Device

A storage device is any computing hardware that is used for storing, porting and extracting data files and objects

Information storage can either be temporary or permanent

They can either be internal or external to a computer or server

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Formats of Data

A format is a pre-established layout for data

There are many ways in which data can be formatted:

Text

Audio

Animations/ Videos

Images

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Access Method

An access method is a program or hardware mechanism that moves data between the computer and an outlying device

Also used when referring to the mechanics of placing or locating specific data at a particular place on a storage medium

Also used to describe the way that data is located within a larger unit of data

An access method is also an application program interface {API} hat a programmer uses to create or access data sets or to read from or write to a display terminal or other output devices, e.g:

Virtual Sequential Access Method {VSAM}

Virtual Telecommunication Access Method {VTAM}

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Access Speeds

Access speeds are measured in bytes per second {Bps}

It means how fast one can gain access to data and information stored in a particular storage media

Slow devices have speeds measured in thousands of Bps {kBps}...

... E.g floppy discs {can save/ read data at a speed of 60kBps}

devices have speeds measured in millions of Bps {MBps}...

... E.g hard disks {can save/ read data at a speed of 300 MBps}

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Data Access

Data Access refers to software and activities related to storing, retrieving, or acting on data housed in a database or other repository

Data access involves authorization to access different data repositories

Can help distinguish the abilities of administrators and uses

There are three types of data access: sequential access, random access and serial access

Sequential Access - Data is read from the beginning in the order in which it is stored

Random Access - Data is accessed directly

Serial Access - Data is read from the beginning and every data stored must be read until the data you want is found