Chapter 3: Storage devices and media (Part 1):

Identify the importance of secondary storage such as Hard Disk Drive:

• Safeguard against lost of data due and Backup

• Safeguard against copyright

• Safeguard against having computer components going bad or malfunction

• Safeguard against damage caused by hackers

Two types of storage medium:

• Fixed: installed internally

• removable

• Optical Storage

• Laser reading base Storage

Two method of accessing data used by storage medium:

• Serial (sequential Access)

• Queue (First in First out access)

• Top down access (Structured access)

• Direct (Random Access)

Two characteristics of Serial (Sequential access):

• Files are stored one by one in a sequence

• Stores files so that they can instantly be accessed

• Must search through the files one by one until you get to the one you want.

• Direct Access of data using search indexing

Two characteristics of Direct (Random access):

• Stores files so that they can instantly be accessed

• No need to search through files to get to the one you want

• Files are stored one by one in a sequence

• Data are to be stored alphabetically and sorted in order

Two Examples of Serial (sequential Access) Method:

• Magnetic Tape

• Flash drive

• Cassette Tape

• CD ROM

Two Examples of Direct (Random Access) Method:

• Magnetic Tape

• Flash drive

• VHS Tape

• External Hard drive

Two Examples of Magnetic Storage Media

• internal hard disk drive

• Flash drive

• DVD ROM

• Portable hard disk drives

Two Examples of Optical Storage Media

• Blu-ray

• Flash drive

• DVD ROM

• SSD

Difference between Main Memory Storage vs Secondary/Backing Storage (Q1):

• Secondary: Usually used to store data while it is being processed by the CPU.

• Main Memory: Data's are hold permanently

• Secondary: Temporary holding data

• Main Memory: Usually used to store application software, operating system software, files etc.