01 - Types of Memory

 1. Human memory is a bit of a mystery but we do understand computer memory! Data and programs need to be stored in a computer. This involves memory. What are the two types of memory?

  Main memory and non-main memory

  Main memory and secondary storage

  CPU and RAM

  Main memory and RAM

 2. What is Main Memory?

  Main memory is any external storage device. Examples are external hard drive

  Main memory is always referring to the hard drive storage

  Main memory is any memory that is directly accessed by the CPU. Examples are RAM and ROM chips.

  Main memory is any main source of memory or storage. Examples are USB drives

 3. Registers and Cache are not considered 'Main Memory' because.....

  ...they reside inside the CPU

  ...they do not store any data

  ...they are not big enough

  ...they are not inside the main monitor of the computer

 4. Secondary storage is used for holding large amounts of data and programs long-term, but can only be accessed relatively slowly. (e.g. an external hard drive)



 5. Volatile memory is .........

  a type of memory that resembles a volatile (easily evaporating) chemical element

  a type of memory that never loses its data once the power is shut down

  a type of memory that loses its data once the power is shut down or interrupted

  a type of memory that is most likely to go up in flames if exposed to solvents

 6. Secondary storage is almost always (1)______________________ while Main Memory (like RAM) tends to be (2)____________________

  (1) Volatile (2) Non Volatile

  (1) Non Volatile (2) Volatile

  (1) Volatile (2) Volatile

  (1) Non Volatile (2) Non Volatile

 7. Read the excerpt below on 'primary memory' and fill in the blanks:
The following are all types of primary memory listed in order of 
closeness to the CPU:

4.virtual memory

The closer a memory type is to the CPU, the _______________________

. However, the closer it 
is to the CPU the smaller and more expensive it is. Each type of 
memory is limited by their speed, size, cost and position in 
relation to the CPU.

  heavier the components that make up the parts

  quicker the CPU can access the instructions and execute them

  lighter the instructions in terms of their general make up

  slower the CPU is to access instructions

 8. Can you name the definition? _________ is the time it takes for components to respond to a request (read the rest of the excerpt for the context)
____________ is the time it takes for components to respond to a 

There will be a short delay, even a few milliseconds between 
asking the computer to execute a program and it finding the files
in the memory. The circuitry that makes up primary memory is very
fast, but not as fast as the CPU clock speed. 

Some instructions are copied into cache to make them more quickly 
available to the CPU.



  Computational Power

  Paralllel Processing

 9. Virtual memory is a section of volatile memory created temporarily on the storage (e.g. hard drive) drive. It tends to be created when ....

  a computer is running many processes at once and RAM is running low.

  a computer is unexpectedly free and RAM is abundant

  a computer is under attack from a virus

  a computer wants to go undercover and adopt a 'virtual' identity

 10. Read the excerpt below on Magnetic tape that was a key part of the computer storage revolution. The magnetic tape being referred to here is likely to be volatile.
========Interesting facts =====================
*refer to the image

Magnetic tape allows for inexpensive mass storage of information and 
is a key part of the computer revolution. The IBM 726 was an early 
and important practical high-speed magnetic tape system for 
electronic computers. Announced on May 21, 1952, the system used a 
unique ‘vacuum channel’ method of keeping a loop of tape circulating
between two points, allowing the tape drive to start and stop the 
tape in a split-second. The Model 726 was initially sold in 1953 
with IBM’s first electronic digital computer, the Model 701, 
and could store 2 million digits per tape—an enormous amount at 
the time. The 726 rented for $850 a month.