QUESTION 1: Describe the concept of absolute units and relative units. Specifically describe the em and ex units.
CSS properties are often used to establish values of length for various elements of a website or app. Some of the most common measurements used in styling with CSS are margins, padding, font-size and various border specifics for box properties. For coding, length measurements consist of a number and a unit distinction. These units will vary depending on whether the designer is using relative or absolute length measurements, but no values can be absent.
Absolute lengths use specific measurements that do not rely on any other defined elements to establish length. Units used for absolute measurement include inches (in), centimeters (cm), points (pt) and pixels (px). There are other absolute measurement units, but absolute length is most useful for print media or devices with lower resolution.
Relative length units are dependent upon a parent property with the stylesheet. This makes relative units ideal for coding websites or other applications that are intended to be view on high-resolution devices with various screen sizes. When using relative measurement units, the most common unit is em. This unit originated as a typographic measurement based on the letter M in the current font being used. For example, when you establish font size in your css document, then the measurement of 1em becomes the new font size for the element. However, if you are nestling elements within elements, it is important to remember that every em specifying font size will by multiplied with the other ems established in the document. For this reason, the value of em can be inconsistent depending on the elements being used in that section of the page. The less commonly used relative measurement is the ex unit. This unit refers the x-height of the current font. This x-height is based on the vertical measurement of the x in the current font. This is true even if the current font does not include the letter x.[Need an essay writing service? Find help here.]
QUESTION 2: Describe the text-align, text-decoration, and line-height properties.
The various design elements available for use in CSS are very similar to basic HTML code elements. However, CSS can be applied and edited without the need to change a large amount of coding in the primary document or application. The text-align element styles the text in the specified section (if applicable) by establishing where it should be placed within the element or page. Just as with a print document, website and application fonts can be aligned in various ways; most commonly left, right and center.
There are several elements that can be controlled by the text-decoration property. Just a with any other element in your stylesheet, this property can be use to establishing overall styling or only just a portion of a page or app. There are values within the text-decoration property that allow underline, overline, line-through and none. As many web browsers automatically underline and color a hyperlink, the text-decoration property and its children (text-decoration-color, text-decoration-line and text-decoration-style) can help the programmer ensure that their project maintains the styling as it was intended rather than picking up default values from the browser or other intermediary code.[“Write my essay for me?” Get help here.]
The line-height property specifies the line height of an entire document or specified section. This property can be either relative or absolute, depending on the measurement units used in the code. For absolute values, a line-height can be a specific length in pixels, inches or other accepted CSS units. If a page or app is likely to be viewed on devices with varying screen sizes and resolution capabilities, then a relative line-height can be established using percentages or a number value that will be multiplied by the current font size.
QUESTION 3: What is dithering? Why does it occur? How can it be avoided?
Dithering is not as much of an issue in web design as it was when both web browsers and bandwidth didn’t allow for a wide choice of colors. When the web first moved beyond simple text pages, designers had to find a way to improve image quality and color perception. Spatial dithering is a technique that uses two colors mixed evenly together, causing the human eye to see an “average” of those two colors. Temporal dithering is – and was – less common. It worked to improve the perceived quality of images and colors on low-quality displays by using frame rate control. Now that most browsers and devices can handle millions of colors more precisely, dithering is rarely used and is not often a problem. However, there are still low-quality devices that have problems with subtle gradient shifts so designers still need to be keep an eye on their code in regard to dithering. If you are designing for high-definition screens and all you have to work with is a low-definition image, you run the risk of your image looking even worse than it actually is. For image smoothing, dithering can still sometimes be useful to make a lower-quality image appear to be of higher quality on a high-definition screen.
QUESTION 4: Give a brief overview of forms and how they work. Include a description of the Common Gateway Interface and CGI scripts.
Common Gateway Interface (CGI) is a protocol used to allow designers to create web forms that interact with a database or other background application. CGI scripts can be written in many web languages, but the sequence by which the script works is generally the same. The designer creates the code for a form. This code can be as simple as a single line or two establishing name-value pairs. Based on the code chosen, a form is created for a user to enter information. Once that information is entered, your CGI script is designed to parse out the values and either use a GET or POST query string. After the CGI script sends the data to where it was intended to be sent, a response is sent back to the user. This is usually done via an HTML page created dynamically on demand.
An example of CGI script used for forms is a small form for a website or blog that allows users to be added to an email list. The user general enters their name and email address, when they press submit, the CGI script communicates with the database application that is managing your mailing list. The name and email are added to the database for later use and the user is sent to a confirmation page or given some other indication as a “reply” from the server that the user’s information was successfully added to the mailing list.[Click Essay Writer to order your essay]
QUESTION 5: Explain the function of CSS positioning properties.
The position property in CSS allows for establishing alternate rules for specific elements within your page or app. There are four values for the position property: static, relative, fixed and absolute. Within these values, top, bottom, left and right can also be specified, but they will only work if the position property is set first. An element positioned as static simply flows with the regular layout of the page and is not affected by the further positioning values. The relative value allows the coder to set top, right, bottom and/or left values, moving the image away from its default normal position. An element defined with a fixed position will always remain in the exact same place on the viewer’s screen, regardless of scrolling. When the position:absolute value is specified, the element will be position relative to the closest ancestor element. However, if no positioning elements are present on which to determine the value, the element will act as a fixed element, remaining in the same position regardless of scrolling. The CSS positioning properties are often useful when scripted animation effects are desired. There are many properties that can be established within the positioning properties, allowing for coders to account for text overflow, specify margins or determine the type of cursor displayed to the user. Rather than using basic HTML or trying to integrate frames, the CSS position properties allow a coder to establish a hierarchy of design that applies to all of a project or whichever specific piece is desired.