the torture will stop when moral improves. binary code is the basic computer language based on...
TRANSCRIPT
COSC 101B
The torture will stop when moral improves
Review
Binary code is the basic computer language
Based on circuit being open or closed Open circuit: No electricity passes=0 Closed Circuit: Electricity passes=1 This represents 1 bit of information▪ A bit has only two states to choose from▪ True or False▪ Yes or No▪ 1 or 0
Add up the Bytes to make a meal
Bits are then organized into groups 4 bits = 1 Nibble 8 bits = 1 Byte 1024 Bytes = 1 Kilobyte 1024 Kb = 1 Megabyte 1024Mb = 1 Gigabyte 1024 Gb = 1 Terabyte
Time keeps ticking by . . .
Processor speed based on hertz System clock is a quartz crystal through
which electricity passes:
The crystal vibrates at a set frequency, called Hz
Processing happens on every vibration Current Olin 212 lab machines process
every 2.83 billionths of a second
Let the races begin . . .
System Speed is determined by four factors: Processor speed Speed and amount of RAM (Random
Access Memory) Amount of Cache, measured in Bits not
Bytes Front Bus Speed
RAM: Not a mean animal
Types of RAM Physical RAM▪ Volatile▪ Located on Mother board and can usually be upgrade
Virtual RAM▪ Temporary usage of available Hard Drive space
Cache▪ Volatile▪ Located on processor and not normally upgradable
Flash▪ Only non volatile RAM▪ Flash cards for cameras and USB drives are examples
ROM: Not a Ferengie (None of you
got that, right?)
ROM Read Only Memory Preloaded from factory Holds OEM specs on computer hardware Holds basic Operating System that runs
start up and looks for loaded Operating System
CMOS: Not an Alien Monkey
Complimentary Metallic Oxide Semiconductor (CMOS is fine for tests) Holds Date and Time Holds basic system set up information POST: Power On Self Test Volatile▪ Requires a lithium battery for power
Hardware, but not from Lowes
Anything you can touch Four basic categories
Processing▪ CPU, RAM, ROM, CMOS, Motherboard
Storage▪ Storage devices, both internal and external▪ Removable Storage devices such as DVD’s and USB
drives Input▪ Keyboard, Mouse, microphone, scanner, etc
Output▪ Monitor, printer, etc
The output basics . . .
Monitors Resolution measured in pixels per inch
(PPI) Two main types▪ CRT – Cathode Ray Tube (looks like old TV)▪ LCD – Liquid Crystal Display (flat panel)
Other types▪ LED (newest technology)▪ Projector▪ Plasma – (don’t let it burn in!)
Other output basics
Printers Resolution measured in DPI (dots per inch) Several consumer grade printers▪ Dot Matrix (low quality, low cost)▪ Ink Jet (medium quality, expensive ink)▪ Laser (high quality, expensive and expensive
toner) Commercial grade▪ Thermal (very high quality, very expensive)▪ Plotter (low quality, mainly used for architectural
plans)
In and Out basics
Modems Modulator/Demodulator Used for connecting computers to external
networks, like ISP’s Formerly used on telephone lines, now DSL and
Cable▪ Max telephone speed 53Kbs by Federal Law▪ DSL 256Kbs, Cable up to 1.5Mbs
Touch Screens▪ Common in ATM’s and self check out devices▪ Popular with personal devices (cell phones and
tablets)
Scanners
Input devices Several types
Flatbed scanners Handheld scanners Barcode readers OMR-Optical Mark Reader▪ Used to grade standardized tests
OCR – Optical Character Reader▪ Used with text to speech software
Moving on to the new . . .
Secondary storage devices Represent “permanent” storage – Non
Volatile!▪ All devices can fail, some less likely than
others Most are moveable▪ External or removable media (more later)
Some are not so moveable▪ Internal hard drive (have to open computer to
get it)
Secondary Storage: Part Two
Divided into two basic categories Magnetic▪ Information stored as a charge▪ Negative charge = No or 0▪ Positive charge = Yes or 1
Optical▪ Physical surface of disc broken into pits and
lans▪ Lan = No or 0▪ Pit = Yes or 1
Magnetic Storage
Magnetic: Hard drives▪ Internal drives▪ External Drives▪ Hard Disc Stacks
Digital Tape▪ Usually used in Enterprise environments for
back up storage USB drive▪ Inexpensive way to back up data and have
extreme portability
Magnetic Types Part Two
Internal Hard Drives Size currently available is well into Terabyte
range Are susceptible to Head crash▪ What happens when Read/Write head makes
contact with disc▪ Can be caused by:▪ A fingerprint▪ A smoke particle▪ A human hair
Available in Solid State format (no moving parts) which are not susceptible to Head Crash
Magnetic Types Part Three
External Hard Drive Available up to several Terabytes Normally connected via USB (newest
connections USB2) Inexpensive and easy to use Still susceptible to Head Crash
Magnetic Types Briefly . . .
Floppy Drives 3.5 inches, up to 1.44 Mb storage Rarely used
Zip Drives Up to 250 Mb storage Rarely used
Digital Tape Up to 800 Gb Storage Primarily used for commercial backup
Magnetic types briefer still . . .
USB Up to several Gb of storage (in excess of
20Gb now available) Very convenient Less likely to fail Unfortunately easy to misplace.
Hard Disc Stack Purely commercial Moveable large storage (several
Terabytes)
Optical Storage
CD Up to 720 Mb of Storage CD ROM▪ Read Only Memory▪ Many programs come on CD ROM
CDR▪ Recordable, but only once
CD RW▪ Recordable, many times
Optical Storage, The Sequel DVD
Up to 17 Gb Storage DVD ROM▪ Read Only Memory▪ Movies also come in this format
DVD R▪ Recordable, but only once
DVD RW +/-▪ Recordable, many times
Blue Ray▪ Up to 60 Gb of Storage, primarily video media currently
What’s Next?
Holographic Data storage Uses multiple lasers to read multiple
angles Up to 2 Tb of storage
Protein Coated Disc Uses light sensitive genetically
engineered microbes to store data Up to 50 Tb of storage
Adding Soft to the system
Software basics All of the instructions that run the
computer All of the programs you use Must be written in computer language Nothing that you can touch
Two main categories System Software Application Software
All Systems GO!
System Software Required to run system Little input required from user Three subcategories▪ Operating Systems▪ Utilities▪ Drivers
Operating Systems
2 basic categories Text base▪ DOS (Disk Operating System)▪ First OS for PC’ss▪ Still works on current machines
▪ Linux Graphical User Interface (GUI)▪ Windows▪ Mac OS
Operating Systems
OS Functions Provide a user interface▪ A way to interact with the machine
Manage resources▪ Control how much RAM is being used by
which programs as an example Run Programs
Utilities: not your average bill
Utilities Used to maintain system or improve
performance▪ Anti Virus▪ Anti Spyware▪ Anti Adware▪ Disc Cleanup▪ Disc Defragmentor
Let’s be careful out there
Malware: why you need certain utilities Viruses▪ Normally delivered through email as an
attachment▪ Do not open attachments unless you are sure
what they are Trojans▪ Programs that pretend to be good, but are bad▪ Example: Waterfall.scr was supposed to be a free
screensaver of a waterfall, but contained malware that deleted files and allowed remote connection
Worms▪ Enter through security holes in the OS
Spyware is not James Bond’s suit
Spyware Loaded without user knowledge Can be gotten from any website Simply hitches on to the web site
download and snuggles into your computer
Can cause it to run slowly or keep some programs from running at all
Can also relay information back to programmer
Adware: they are looking for you
Adware Downloaded from visited site without
user knowledge Can cause unintended Pop Ups Can hijack your browser to force you to
certain sites Can return information from your
computer to the programmer Can cause the system to run slowly
Drivers: not all of them are bad
Drivers Software for hardware Every piece of hardware requires a
driver Instructs the OS on how to use the
hardware
Other Utilities
Disc Cleanup Removes temporary files taking up
unnecessary space Disc Defragmenter
Puts relevant data in the same sectors on the Hard drive
End of today’s fascinating Foray
Test on Thursday.
There will be no mercy
See you then