Continue Khan Academy programming using Java Script https://www.khanacademy.org/cs
- 1 Monday
- 2 Tuesday
- 3 Thursday (Lab)
- 4 Technology Friday
An Introduction to Data Types
- A literal is an actual fixed value (as you would normally write it) e.g. 75, -30.333, 'z', "This is a text string".
- A constant uses a symbolic name to represent a fixed value, e.g. #define PI 3.14159265. The symbolic name is used to refer to the value throughout a program. The value remains fixed and may not be altered by the program.
- A variable uses a storage location in computer memory with an associated symbolic name (identifier) which contains a value that can be read and modified, e.g. var ClassAverage = 95;
Common data types:
- integer (whole numbers, + or -ve)
- floating-point (fraction, real or decimal numbers)
- bool (binary value - 1=true 0=false)
- char (a single ASCII character)
- string (a sequence of characters)
ASCII - American Standard Code for Information Interchange A character-encoding scheme originally based on the English alphabet. Encodes 128 specified characters - the numbers 0-9, the letters a-z and A-Z, some basic punctuation symbols, some control codes that originated with Teletype machines, and a blank space - into 7-bit binary integers.
Purpose of Data Types:
In computer programming, a data type or type is a classification data which determines:
- the possible values for that type
- the operations that can be done on values of that type
- the meaning of the data
- the way values of that type can be stored
Strong and Weak Typed Languages
C and C++ are examples of strongly typed languages.
Onward With KA
- Closer look at Variables project Spin-Offs
- Intro to Animation
Introduce weekly log book/journal activity.
Feedback from variables spin-offs review.
- Intro to Animation
- Terrific Text
Once a computer has been infected, it proceeds to encrypt certain types of files stored on local and mounted network drives. The *ONLY* way of retrieving the contents of an encrypted file is either retrieving the original from backups (if available!), or paying a ransom.
The ransom is normally paid using the Bitcoin anonymous currency.
Based upon the current bitcoin exchange value of $960, this is $40,250,880 USD.
BEWARE THAT CRYPTOLOCKER IS CONSTANTLY BEING UPDATED - NEW VARIANTS RELEASED REGULARLY!
Protecting Yourself from CryptoLocker
- Make sure you are running Anti-Virus software that is up-to-date
- Never click on links in email messages sent to you that you were not expecting to receive - especially spam. If in doubt, email the sender to confirm the the message content.
- BACKUP BACKUP BACKUP - always ensure you have a backup system that works.
Sony, North Korea and the NSA
There is evidence that the NSA knew that North Korea was behind the attack - or at least last. There is also evidence that it might have been an "inside job".
Cryptography - Part 2
- WW2 Enigma Machine (10:01)
- Claude Shannon's Perfect Secrecy (4:13)
- Random vs. Pseudorandom Number Generators (6:40)
- Diffie-Hellman Key Exchange (8:37)