There are two main types of digital images: vector graphics and bitmap (raster) graphics. Vector graphics use mathematical expressions to build and display an image from points, lines, and curves, allowing it to be scaled and resized without losing quality or resolution. Bitmap images are made up of pixels and are resolution dependent, so scaling them up will reduce quality. Factors like compression, resolution, and how an image is captured or output can also impact its quality and file size.

1. What do you know about digital graphics?
Digital images: Two kinds of image
1 Vector
2 Bitmap (Raster)
Vector Graphics
Made of points, lines and curves- the image is built and
displayed through mathematical expressions
It can be scaled (re-sized) and will not lose clarity or quality.
Resolution-independent-can be printed at any resolution.
Common file formats: ai, cdr, ps, pdfs
Common vector graphic programmes: adobe illustrator,
CorelDraw, freehand.
Common uses of vector graphics: Drawing, illustrations,
cartoons.
Bitmap (Raster)
Made up of pixels
Resolution- dependent- it cannot be scaled up without losing
quality
Common bitmap files: jpg, jpeg, gif, png, tif, tiff, bmp
Common bitmap programmes: paint, Photoshop
Common bitmap images: Photographs and painting.
Pixel
The smallest part of a bitmap (raster) image. This pixel will
have a single colour. If you zoom in far enough, or scale a
bitmap image up you can see its pixels.
OR

2. The smallest controlled element of the screen. Each pixel on
the screen emits red, green and blue light. By changing the
level of each colour (red, green and blue) your screen is able
to produce every possible colour.
Factors which impact image quality
Compression: This is when you try to reduce the size of a file,
perhaps to make it easier to send to someone else.
By compressing the image you lose data, this means you lose
quality
Resolution: this is the size of a image.it is how many pixels
tall, and wide, an image is
The higher the resolution = the better the quality
However this means the file size is larger
Resolution only applies to bitmap images.
Image capturing
Scanning an image which has been drawn. This image
cannot be resized without losing quality
Digitally drawing an image is Photoshop with a sketchpad
and stylus. This image can be resized, providing it is being
drawn as a vector image.
Using a digital camera simply takes a photo which is saved
digitally. Stored as a bitmap image, so will lose quality if resized.
Output
How an image will be outputted often determines the kind of
image it needs to be.
Outputs: print (paper), screen and online

3. Print: printing uses the CYMK colour pallet (cyan, yellow,
magenta, Black)
Screen: use pixels to displays and image, so uses the RGB
colour pallet (Red, Green and Blue)
Storage
File size: the larger an image is, or the higher its resolution,
the larger the file is:
Harder to email
Longer to download
Takes up more space in a computer memory’s