| A | B |
|---|
| device pixel | is the tiniest physical unit in a display. |
| Screen density | refers to the number of device pixels on a physical surface. It is often measured in pixels per inch (PPI). |
| pixel density | refers to the number of device pixels on a physical surface. It is often measured in pixels per inch (PPI). |
| Resolution | a simple count of the number of pixels across the entire width and height of a device. |
| Pixel density | a good indication of how clear the device display will be. |
| Viewing distance | can affect the perceived pixel size. |
| bitmap pixel | is the smallest unit of data in a raster image (PNG, JPG, GIF, etc). |
| Web Images | Besides its raster resolution, an image on the Web has an abstract size, defined in CSS pixels. The browser squeezes or stretches the image based on its CSS height or width during the rendering process. |
| CSS | defines that raster images (such as photos) are, by default, displayed with one image pixel mapping to 1px. |
| CSS px | not defined as a constant length, but as something that depends on the type of device and its typical use. |
| Pixel density | can be queried using JavaScript |
| CSS Media Queries | can be used to serve up the appropriately sized assets. |
| responsive web design | design for the smallest viewport first and then work up towards the larger viewpoints. The design and content can be enhanced as you work upward. |
| fixed-width layouts | the width of the site is bound to a certain number of pixels. |
| Fluid or liquid layouts | define dimensions in percentages rather than pixels. |
| div tag | HTML tag that in most cases acts as a container for text, images, and other page elements. |
| container div tag | first div tag on a page |
| em unit | unit of measurement in the field of typography, equal to the currently specified point size. The name of em is related to M. Originally the unit was derived from the width of the capital “M” in the given typeface. |
| Absolute size | Sets the text to a specified size Does not allow a user to change the text size in all browsers (bad for accessibility reasons) Absolute size is useful when the physical size of the output is known |
| Relative size | Sets the size relative to surrounding elements Allows a user to change the text size in browsers |
