the web. web servers and file transfer protocol (ftp)

The Web

Web Serversand File Transfer Protocol (FTP)

A web server is simply a computer containing files and folders not unlike your computer at home.

File

Folder

My computer at home.

Files & Folderswithin another Folder

The Difference is:

1. The files are often “special files” that tell a web browser what to do.

2. The files and folders are broadcast for the world to see.

Naming Conventions

When dealing with web servers and theinternet, stick with standardized namingconventions for your files and folders.

This means:• Use no special characters (!*.&^~$%#) or spaces.• Use only letters, numbers, the dash ( - ), and

the underscore ( _ ).• Assume everything is case sensitive.

Bad naming examples are: “big bird.jpg” or “joe&12.htm” Good naming examples are: “big_bird.jpg” or “joeAnd12.htm”

Screen Resolutionand monitor size

When you buy a bigger TV, you get a bigger picture.

19” screen 27” screen

When you buy a bigger computer monitor you get More workspace.

20” monitor 30” monitor

Screen Resolution is a very critical issue when dealing with the web.

To help insure your site will be viewable on as many monitors as possible, keep your site’s width to no greater than 1000 pixels.

A safer standard is 800 pixels wide by 600 pixels high.

Image Resolution

When dealing with the web, what resolution (dpi / ppi) should your raster images be?

72 dpi / ppi

2 x 3 inches @ 20 dpi

(20 x 20) x (2 x 3) = 2400 pixels

2 x 3 inches @ 45 dpi

(45 x 45) x (2 x 3) = 12150 pixels

2 x 3 inches @ 72 dpi

(72 x 72) x (2 x 3) = 31104 pixels

2 x 3 inches @ 150 dpi

(150 x 150) x (2 x 3) = 135000 pixels

Color Modes

There are three Color Modes that we are concerned with in this class.

1. Grayscale - one channel

2. RGB (Red, Green, Blue)

- three channels

3. CMYK (Cyan, Magenta,

Yellow, Black) - four channels

When dealing with the web, what Color Mode should we use?

RGB

The RGB Color Mode is based on the Additive Color

Model of Light.

Monitors, Televisions, Projectors and other light based systems use this color model

Image / File Formats

There are two main Image / File formats we will be concerned with in this unit.

1. JPG 2. GIF

The JPG file format is a method of compression commonly used for photographic images allowing a tradeoff between file size and image quality.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Quality: 50Size: 15 K

Quality: 10Size: 4 K

Quality: 1Size: 1.5 K

The GIF file format uses lossless compression, but is limited to only 256 colors. Therefore, Gif is not suitable for photos, but is well suited for simple graphics and logos with solid areas of color.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Both GIFs and JPGs can easily be exported from Photoshop using FILE >> SAVE FOR WEB.