Computational Thinking & Scratch – Intro to Computer Science(week 0)

Computer science is about problem solving

 

           H              I (letter ascii)

          72             73 (decimal numbers)

      1001000        1001001 (binary 8 bit)

 

Abstraction – converting lower level details into more simplified version and focus on problem solving

Since there are so many languages that cannot be represented by 8 bit(256 different type of possibilities), now we use Unicode or utf-8 which uses 16 bit(2 to 16th power or 65536 different possibilities).

 

Rgb – a dot, pixel, uses three byte per pixel, how many red, how many green, how many blue per pixel.

An image is a group of pixels using three bytes(24 bit) in total of kilobytes, megabytes, and so fourth.

A video is a collection of images, 24 fps(frames per second) example, showing 24 images per second, showing a sequence of static images and makes it look like a moving video.

Videos -> images -> colors -> bits -> frequency of electricity

 

Input -> algorithms -> output 

Pseudo code – a simplified programming language

 verbs here are functions, questions like if else if are conditions, smith is among names is Boolean expression, go back to step2 loops

Gigahertz – GHz is a unit of measurement for AC(alternating current) or em(electromagnetic) wave frequencies equal to one billion hertz.