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Charles Babbage (1791-1871)
- Math Professor at Cambrige
- Difference Engine (1821)
- Analytical engine (1843)
Ada Lovelace
- First computer programmer
- Wrote plan for analytical engine - Bernoulli Sequences
Difference Engine
Required 25,000 parts, weighed 15 tons
Never finished it
Analytical Engine
- Mother of all computers, conceived of by Charles Babbage
- Also, never finished
- Could (theoretically) be programmed with punched cards
- Could carry out any calculation to 20 digits of accuracy
Alan Turing
- him and team completed Colossus to break Enigma (German military cipher machine)
- Turing test - basic test for AI
Colossus
first electronic digital computer
ENIAC
- Electronic Numerical Integrator and Computer
- calculate trajectory tables for new guns
- John Mauchly and J. Presper Eckert
Sperry and UNIVAC I
company and the first general-purpose computer
Admiral Grace Hopper
- Invented the compiler,ca 1952
- Created COBOL one of the first programming languages
- Coined the term "debug" (actual moth stuck in the Harvard Mark II computer)
Vacuum Tubes
Cylindrical glass tubes that controlled the flow of electrons, used in the first generation of computers.
Transistors
- replaced vacuum tubes (starting 1956)
- small electrical devices that could receive and amplify radio signals
Silicon chips (integrated circuits)
- replaced transistors (by mid-1960's)
- tiny electronic brains in devices, handling tasks like processing data and controlling electricity flow
Computers today
- portable, smaller, faster
- fragile and expensive to upgrade/repair
- Proprietary hardware
Operating system
system software that manages computer hardware and software resources and provides common services for computer programs
VMWare Fusion. parallels, virtualbox
software that lets you run different operating systems, like Windows or Linux, on your Mac computer at the same time. It's like having multiple computers inside your Mac, all running together.
embedded computers
a special-purpose computer that functions as a component in a larger product
- controlling temp and humidity
- monitoring heart rate
- monitoring house security system
Freeware
software that is free
- can be unsophisticated
- can be sophisticated: Firefox, VLC media player, etc.
Open Source
Free software and source code
- free download, modify, improve
Project Gutenberg
Repository of 60,000+ free texts in the public domain out of copyright
- mostly english
- many translated in public domain
- mostly direct download
Byte
8 bits
Kilobyte (KB)
1 Thousand bytes
Megabytes (MB)
1 Million bytes
Gigabytes (GB)
1 Billion bytes
- storage value decreased over time
Terabytes (TB)
1 Trillion bytes
Petabytes (PB)
1 Quadrillion bytes
MHz
megahertz
GHz
Gigahertz - the unit in which the speed of the CPU is measured
- similar to clock ticks
- 1 GHz: capable 1 billion machine cycles per second
- used by intel and recently AMD
Moore's Law (Gordon Moore)
- modern trend not true physical law
The number of transistors that can be inexpensively placed on an integrated circuit doubles every two years.
- exponential growth can't continue forever. Miniaturization eventually approach atomic sizes
Moore's Law variants
transistors, processing speed, and storage capacity doubles every 18 months
RAM
Random Access Memory
- temp store program instructions and data
- unique addressed and data stored in any location
- quick info retrieval
- not remain of power goes out
ROM
Read only memory
Cache
Small block of very fast memory (512 Kb - 2 Mb)
- speeds up date transfer (holds frequently/ recently used data and instructions)
For finding instructions/ processing data
- checks RAM first and stores frequent/ repeated info in Cache for quicker access
ASCII (binary code)
American Standard Code for Information Interchange
- most widely used
Unicode
A coding scheme supporting 65,000 unique characters
ALU
Arithmetic Logic Unit
- electronic circuitry executes arithmetic and logical operations
(addition, subtraction, multiplication, division)
Dvorak Keyboard
keyboard layout to improve typing speed (hands dont have to move much)
- developed in 1936
resistive touch screen
edges emit horizontal and vertical light beams
capacitive touch screen
create electromagnetic field, blocked by the electromagnetic field of your skin and allows for multi-touch input
Touch screens
Resistive and capacitive
- input and output from same device
- convenient
- common on smartphones, tablets, and some laptops
Accelerometer
detects vertical or lateral motion, converts to a digital signal
- smartphones, nintendo wii-mote, Monome
Optical input methods
Input methods that use barcodes, QR codes, optical mark recognition, or optical character recognition
Bar codes
-Universal Product Code (UPC): pattern of vertical marks
- bar code reader reads horizontally
QR Code
Quick Response Code
- code stored horizontally and vertically ~4000 alphanumeric characters
- typically used for web addresses
OMR
Optical Mark Recognition
- machine senses mark on paper
- fill-in sheets
- scantron
OCR
optical character recognition
- that involves reading text from paper and translating the images into a form that the computer can manipulate
MICR
Magnetic Ink Character Recognition
- readable by humans and machine
- typeface developed by American National Standards Institute
RFID
Radio Frequency Identification
- Commonly used in employee/Student ID badges, theft prevention systems, many others
- Briefly used in credit cards, now rare
- Potential for misuse, invasion of privacy
Laser printer
use a laser beam to create patterns of electrical charges on a rotating drum, attracting colored toner powder that is then fused onto paper
- faster and more expensive than inkjet printers, offering high-resolution print output.
Inkjet Printers
spray ink onto paper to make text and pictures. They print slower than laser printers but offer better color quality at a lower cost. The liquid ink they use makes colors more vivid and accurate compared to color laser printers, which use a mix of different colored powders.
Magnetic disks
Random data access and secondary storage
Floppy disks
Provide inexpensive, portable storage
Hold too little data for modern purposes
Hard disks
non-removable, rigid disks that spin continuously and rapidly
-provide much faster access than a floppy disk
US copyright law
- Protect ideas and creative works.
- Last for 70 years after the author's death (or up to 120 years for works created by companies).
- Originally lasted for 50 years plus the author's life until the Bono Act of 1998 extended it.
Patents
- Safeguard inventions.
- Generally last for 20 years from the date of application
Sony vs. Universal Studios
- Landmark 1984 copyright case
- The Movie industry tried to prevent the sale of video recording technology for home use.
Arguments:
- home recording of televised movies would hurt box office returns and ad revenue from future broadcasts
- claimed Sony should be liable for potential misuse by its products' owners
outcome:
sale of video recording technology for home use was legal
Jammie Thomas Case
In the Capital Records et al v. Jammie Thomas case, Jammie Thomas was sued for making songs available for download, but a retrial was ordered as it was questioned whether simply making copyrighted material available constituted infringement.
DMCA Safe Harbor provisions
let people freely share information online while still letting copyright holders remove illegal content. Websites hosting user-shared stuff aren't immediately responsible for illegal things users post. But if they don't take down illegal stuff when asked, they could get in trouble.
Aaron Swartz
-Helped develop:
RSS (Really Simple Syndication)
Reddit, Creative Commons
-Founded Demand Progress
Instrumental in halting SOPA
-Legal troubles:
PACER in 2008
JSTOR in 2010
PACER in 2008
- Stands for Public Access to Court Electronic Records.
- The court system charged 8 cents per page to access public records, making about $100 million a year.
JSTOR in 2010
- Faced over 50 years in Federal Prison for Wire Fraud and violations of the Computer Fraud and Abuse Act.
- The person involved committed suicide in January 2013, just two days after a rejected settlement offer.
Fair Use
Fair Use exceptions allow for the limited use of copyrighted content for purposes such as criticism, commentary, parody, teaching, scholarship, or research. However, these exceptions are not absolute, and whether a particular use qualifies depends on factors such as the amount used and its effect on the market.
Abandonware
software that is no longer sold, its company has closed, and it runs on outdated systems. While this often doesn't harm anyone, it can hinder the re-release of nostalgic software, especially games. Sometimes, other companies buy the rights, such as mobile app publishers reviving old games.
Linus Torvalds
Creator of Linux, Git
- Linux distributions (Ubuntu, CentOS, Fedora)
- Local Connection: SCO Litigation, 2003
Linux
an open-source version of the UNIX operating system
an opensource operating system core
Git
Used to track changes in programming files modified by multiple authors
Large repository of open source software
Natural Languages
resemble languages spoken by humans
programming language
falls between machine and natural human language
- examples: c++, JavaScript, Perl, PHP
compiler
translates programming language into machine language
Machine Language
numeric codes that represent data
Software testing
Alpha testing and beta testing.
Alpha testing
trials by internal users and very select groups
Beta testing
trials by external users, usually by volunteers
Software insiders' advice
Never buy version 1.0 of anything
Emulator Programs
can "pretend" to be another operating system or hardware device
- can run programs written for that system
- not all applications work perfectly
- can cause a drop in system performance, especially with resource/graphics intensive applications
- older systems are easier to emulate
Licensing
commercial software is copyrighted so it cant be legally duplicated for distributions for others
- software license
- volume license
Distribution: software is distributed via..
- direct sale
- retail stores
- websites
EULA
End User License Agreement
Device Drivers
Small programs that allow input/output devices to communicate with the computer.
- included with the operating system or bundled with peripherals (mouse, keyboards)
- some devices work without specific drivers, but others require them for functionality
- troublesome drivers often include video and printer drivers
New PC's prioritize compatibility with the latest windows versions over older ones intentionally, not accidentally
Hard Drive Reliability
Hard drives can fail unexpectedly
Automated Backup Systems
- Recommended for forgetful or procrastinating individuals.
- Can back up data every night while sleeping.
- Can remind to back up periodically, like every two weeks.
Multiple Backup Locations
- Relying on a single backup is risky.
- Crucial data should be backed up in multiple locations.(E.g., one at home and another at work, family house, or a storage unit.)
Cloud Backup Services
- Services like Dropbox and Google Drive offer secure backup options.
- Not suitable for storing large files like movies, music, or programs.
Differentiating Data
It's crucial to differentiate between replaceable and irreplaceable data.
- Replaceable: movies, music, ebooks.
- Irreplaceable: personal photos, videos, written documents.
Hard Drive Failure Statistics
Every year, a hard drive has approximately a 12% chance of sudden failure
External vs. Internal Hard Drives
External hard drives are generally less mechanically reliable than internal ones
Laptop Hard Drive Vulnerabilities
Laptop hard drives are more susceptible to damage from spills, theft, and accidents
External Hard Drives
- These are like portable storage units you can connect to your computer.
- They're good for extra space or for moving files between computers.
- However, they can be less sturdy than the ones built right into your computer.
Internal Hard Drives
- These are the ones already inside your computer.
- They're usually more reliable because they're not moved around as much.
- Since they're inside your computer, they're safer from accidents like drops or spills.
Database program
a software tool for organizing the storage and retrieval of information
Database
a collection of organized data that allows access, retrieval, and use of data
- typically composed of one or more tables
-> A collection of related information
-> A collection of records
Record (in a database)
the information relating to one person, product, or event
Field (in a database)
each discrete piece of information in a record
Field Type Determination
- The type of information a field can hold is determined by its field type.
- Also referred to as Data type or Field Data type.
Data Types
- Data types can be categorized into text or numeric.
- Numeric data types include date, GPA, and account balance.
- Text data types include name, major, and outstanding arrest warrants
Form Views (database)
- Form views display one record at a time.
- They are useful for focusing on individual entries.
List Views (database)
- List views show several records in lists, similar to how a spreadsheet displays data.
- They allow for a broader view of data, making it easier to compare multiple entries at once.
SQL (Structured Query Language)
- A standardized language for programming complex queries in database management systems.
- Supported by most modern database management systems.
- Allows programmers and sophisticated users to work across different systems without learning new languages.
- Graphical user interfaces (GUIs) enable point-and-click query execution, insulating users from the complexities of SQL.
Special-Purpose Database Programs
---Specialized database software
---Geographical information systems (GIS)
Specialized database software
preprogrammed for specific data storage and retrieval purposes
Geographical information systems (GIS)
include geographic and demographic data in map form
