Revised: June 2, 2000Browsers
Client/Server Structure of the World Wide Web/Internet
The World Wide Web/the Internet is a world-wide network of computers. Web pages and other files reside on servers -- these servers are designed to be always connected to the Internet, so that the web pages and other files would always be available to people accessing the Internet. When people access the World Wide Web from their personal computer (PC), a copy of the web page on the server is transmitted to the client, the personal computer. These web pages are designed so that when viewed through the use of browsers, such as Netscape Navigator/Communicator or Microsoft Internet Explorer, the web page has the look and feel we associate with web pages -- links to other pages, scrollbars, attractive layout, and so forth. Browsers are programs that reside on the client, in this case the personal computer.
Most of the files (principally those with .html and .htm extensions) on Web servers are ordinary text files, but there are also images, sound files, executables, and so forth.
Web Addresses -- Uniform Resource Locators (URLs)
All URLs have the same structure. Suppose the URL is http://www.erols.com/wpegram/index.html The parts are as follows:
http:// - the protocol (http is by far the most common, examples of others are ftp and telnet)
www.erols.com - the domain name of the computer on which the file resides
/wpegram - the pathname of the folder or directory
index.html - the name of the fileComputers that use the UNIX operating system are case-sensitive and therefore entering the wrong case in an URL may result in being unable to locate the desired web site if the web site is hosted on a UNIX machine.
The main difference between an email address and an URL is that email addresses have exactly one @ sign, and URLs never have an @ sign. In addition, email addresses never have a protocol such as http:// or a www in the domain name; both of these indicate an URL. Both email addresses and URLs never have commas.
IMPORTANT BROWSER FEATURES
Adjusting Size of Text and Images
There are two ways to adjust the size of what you see in the browser. Typically, one does these once on a monitor, and then leaves them alone. The change that affects everything is to change the resolution of your monitor. To change the resolution in Windows, click on the Start button, then choose Settings, then click on Control Panel. In the Control Panel, click on Display, and then the Settings tab. You can then change the resolution of the monitor by moving the indicator for Screen Area. What resolution looks best to you will depend on the size of your monitor and how big you like things to appear. Most people will set a 14" monitor at 640X480. I set my 17" monitor at 800X600, although some would set it at 1024X870.
The other way to affect size is more limited -- it only affects the content you view in the browser and only affects the size of text. In Netscape, one can set the default font size for all web pages by selecting Edit, then Preferences, then clicking Fonts, and then specifying a font size for proportional and fixed size fonts. Alternatively, one can select View, and then Increase Font or Decrease Font. In Internet Explorer, one alters the font size by clicking View, Text Size, and then selecting the desired size. If this has no effect on size, one can select Tools, Internet Options, General, Accessibility, and click the box to ignore font sizes specified on web pages.
Following Links
Generally, text links are underlined and in blue; if you follow the link, the link will be a different color (sometimes web pages are programmed so some or all of this is not true). You can tell when you're pointing to a link because the mouse pointer changes to a little hand. When you point at a link, the location it points to generally appears in the status bar, or in a "tooltip" next to the mouse pointer (again, web pages can be programmed so that this is not true). Sometimes pictures are links, and sometimes different parts of the image point to different pages (images that do this are called "image maps").
Entering a URL into the Location Field
You can leave the http:// off in front of URLs in the location or address box. Netscape will assume .com at the end if you don't type an extension. You may be able to get away with not typing www in some cases. If you don't include a filename, most servers will send the index.htm or index.html file.
First, to change the location field, one must set the focus there. If one starts typing and the focus is not set in the location field, nothing will happen. To set focus, one positions the mouse in the location field and clicks once or twice. One of two things will happen:
1) If any portion of the entire address in the location field is highlighted, then one can replace the highlighted portion by hitting the Backspace Key, the Delete Key, or simply typing in what you would like to have in the field.
2) If the address is not highlighted, then the insertion point will be positioned somewhere in the field and one can use the Backspace and Delete keys to delete one or more characters and can type in additional characters (in either Insert or Typeover mode).
If the entire address is highlighted, one can change to the insertion point mode (mode 2) simply by clicking once where one would like the insertion point to go. Conversely, one can highlight the entire address by double clicking in the location bar, but often a single click will suffice.
Both Netscape 4 and Internet Explorer 4 and 5 use auto-complete to try to guess what you what entered in the location bar. In Netscape, the auto-complete occurs right in the location bar and is highlighted in color. If one doesn't like the choice, one simply keeps typing, and this replaces what is highlighted. In Internet Explorer, the autocomplete occur below the location bar. Auto-complete works by utilizing what one has typed before so if one makes a mistake, autocomplete will suggest the same mistake the next time. For this reason, I recommend, particularly in Netscape, to ignore the auto-complete and type in the address desired. You can turn off the feature in Internet Explorer, but not in Netscape. To turn off in IE, go to Tools, then Internet Options, then Content, then Auto-complete, and check or uncheck where you want autocomplete.
If you receive the address in an email or anywhere else on your computer, you can use standard cut and paste techniques (Control C, Control V) to avoid retyping it.
Bookmarks (Navigator) and Favorites (Internet Explorer)
Bookmarks in Netscape and favorites in Internet Explorer allow you to recall a page without typing in the address. This saves time, particularly because an internet address must be typed exactly right in order to work.
To bookmark a page you are on, click Bookmarks, then select Add Bookmark. However, if you have many bookmarks, it is more convenient to have related bookmarks organized into folders. Although you can drag and drop a bookmark into a folder once you have created the bookmark by clicking Bookmarks, then Edit Bookmarks, some may prefer to put it in the proper folder when you create it. To do this, click Bookmarks, then File Bookmark, and then selected the appropriate folder or subfolder.
To rename a bookmark, click Edit Bookmarks, select (highlight) the bookmark, then Click Edit, Bookmark Properties, you can rename the bookmark by typing in a new name. Alternatively, when you highlight the bookmark, you can right click, and then select Bookmark Properties.
In Internet Explorer, bookmarks are called favorites and one can file them in the right folder by selecting Favorites, Organize Favorites. Internet Explorer can export favorites to Navigator and import bookmarks from Navigator, so you can keep these two sets of files synchronized. The same apparently holds true for cookies, although I haven't used that feature.
Reloading a Web Page
Browsers keep a copy of web pages you have looked at recently in a cache on the hard drive. This allows them to quickly reload the page should you visit it again. The downside of this is that sometimes the version of the page is not the version that is currently on the internet. To force Navigator to reload the page from the web server, you press the Shift button when you click the Reload button. Shift-Refresh in IE is analogous to Shift-Reload in Netscape in that it forces reloading of a web page
ADDITIONAL BROWSER FEATURES
Using Your Bookmark File on Another Client Computer
Click Bookmarks button on location toolbar, then click Edit Bookmarks, then click File on the menu bar, and then click Open Bookmark file. Change to the drive containing your floppy disk, and then open bookmark.htm from the floppy.
Using the History List
To view the history list in Netscape, click Communicator, click Tools, then History (Perry & Schneider, left out the Tools step). In Internet Explorer, click the History icon. The History List in Internet Explorer is more useful because you can view offline, pages that you visited online. Both Netscape and Internet Explorer permit you to delete individual items from the history list and clear the entire history list.
To delete individual items from the history list - When the history list is displayed, right click on the item, and then choose delete.
How to clear the entire history depends on the browser you are using:
Netscape 4 (most versions) - Edit, Preferences, then Navigator, then click "Clear Location Bar" button
Internet Explorer 4 - Choose View, Internet Options, (if control panel is launched, click Internet Options on Control panel), then General tab, then click "Clear History" button
Internet Explorer 5 - Choose Tools, Internet Options, then General tab, then click "Clear History" button
Netscape 3 - requires you to edit the Windows registry which may require you to reload (reload, not restart) Windows if you make a mistake so be careful - The following procedure is from The Internet for Dummies, 6th edition, p. 117 - Start menu, Run, and type Regedit. Double click on HKEYCurrent_User, and then double-click on Software, Netscape, Netscape Navigator, and then URL History. Click on each URL you want to delete to highlight it, and then press delete. Then Exit the program.
Saving Web Page Text to a File
Highlight text, Edit Copy or Control C, Edit Paste or Control V.
Saving an Entire Web Page
Images (and other files such as sound files, executables, word processing documents, spreadsheets, presentations, databases, etc.) are separate files, and are not part of the HTML file, which is a text file. When one saves a web page, the image files must also be saved. In Internet Explorer 5, the image files are automatically saved. In earlier versions of Internet Explorer, and in all versions of Netscape as of this writing (i.e. through Netscape Communicator 4.72), one must explicitly save these other files separately. To save an image, one right clicks on the image and then choosing the save menu item (named differently in Navigator and Internet Explorer.
Opening Up Multiple Windows
You can open up another window to follow a link by right-clicking the link and then select "Open in New Window" from the menu that pops up. You can also create a new window without following a link (click File, and then an option which depends on the version of the software you are using). Although using multiple windows divides the bandwidth of your connection among several windows, this may not slow you down since a lot of the time you are looking at what is displayed in the browser without asking it to do something else.
Search Button
Although this button is a quick way to get to a search engine, it may not be to the one you want. In Netscape, you get to choose from 9 search engines, with the default engine highlighted. It appears that the default search engine changes unless you specify otherwise. In Internet Explorer, you get only the MSN search engine. A better approach seems to be to go directly to the search engine you want by entering the location or by using a bookmark.