To kick-off the year, I’ll be working through CS50: Introduction to Computer Science. CS50 is the largest course on the Harvard campus – and has more than 2,000,000 registered learners worldwide (via edX).
This is my first week 🙂
The first video element was fantastic! I highly recommend watching, even if you aren’t taking the full course. David J. Malan is enthusiastic and clear.
They say computational thinking (fancy scary words) is about solving a problem. Computer programming happens in between the input and output.
I’d heard about binary before, but the visualizations made it much easier to understand.
Computers speak in terms of zeros and ones.
How? Computers are a series of transistors (think: switches).
If the switch operated a light bulb then 💡 Zero (0) = off. One (1) = on
In this manner you can use 3 light bulbs (bits) to count up to 7.
To do this you assume the placements are values as 4 2 1.
- 0 0 0 is equal to 0
- 0 0 1 is equal to 1
- 0 1 0 is equal to 2
- 0 1 1 is equal to 3
- 1 0 0 is equal to 4
- Ultimately when you turn on all three you have 7
If you add one more bulb you can count to
Standard computers use eight bits, for a max represented count of 255.
ASCIIÂ [in full: American Standard Code for Information Interchange] is the standard language chart used to map number values to letters to specific characters.
- Similarly, Unicode standardized emojis into their own visual dictionary.
Fun fact: because numbers are used to represent information, there are designated numbers to represent numbers too – see below: 0-9 = 48-57.
This means, my name in ASCII is: 65 73 68 69 76
- Red, green, and blue (RGB) are a combination of three numbers.
- Images are collections of RGB values.
- Videos are sequences of many images stored together (think: flipbook).
- Music can be represented through MIDI data.
From here we enter algorithms.