Midterm 1 - Results
Basically, most people did pretty good. High grade 98, low grade 48, average about 75.
Rough cutoffs on grades are approximately 85-100 A, 75-85 B, 60-75 C, below 60 D.
The resume assignments were graded based on relative appearance, as judged by all the student TAs.
There will be more to distinguish among the grades on the next assignment.
Sign up now for Pizza with the Prof, Monday October 14, 12PM.
What is the Internet?
Much of the excitement in computing these days is due to improved communications, not faster processing.
The Internet is a collection of computers, some of which are connected to each other directly, but which together form a chain so any computer can talk to any other computer.
What can you do on the Internet?
What is on the WWW?
More than you can imagine! Any data that any person or company wants to make available to the world.
Check the status of your FedEx package.
Look up toll free 800 numbers
Indexes of the WWW built by "web crawler robots" which travel the entire WWW. Examples: Yahoo, Lycos, Alta Vista.
Home pages for hundreds of thousands of people, with whatever they want to say about themselves.
Software and papers to ftp.
Advertizing and special sites by hundreds of businesses.
Who owns the Internet?
Amazingly, no one owns the Internet. Everybody owns their own machine. Basically, to connect a new machine, you must find someone on the net who will let you connect to them. Basically, you will have to pay them enough to pay their expenses for sending your traffic through.
So what is an Internet service provider selling you? Just access to their machine which is on the network.
Because it costs very little for local transmission of small amounts of data, email is essentially too cheap to charge for! Images and voice require more bandwidth.
Since no one owns the Internet, there is great freedom to post whatever information you want.
Internet Etiquette
Because no one runs the Internet, people must police their own behavior. The whole network can survive only if people follow proper etiquette.
Do not fetch large amounts of data that you really don't need. It just slows down the network for everyone.
In an Internet newsgroup, listen for a while (at least a few weeks) before asking a question - likely beginner's questions have been asked many times before, annoying regular readers.
It is easier to send mail to hundreds of people than for them to read your mail. Think carefully whether everyone really wants to see your mail - most people get too much junk mail as it is. Sending junk to a newsgroup is like sending junk mail to thousands of people.
Be very careful in what you say in email - sarcasm or humor is easily interpreted as flaming, and on-line discussions quickly degenerate into shouting. Remember that there is a person on the other end of the line!
Check your email carefully for spelling and language errors - such things look really bad in print.
Be patient and understanding if people do not respond to your mail immediately, or even at all. They are very busy.
Internet buzzwords
The Internet is defined by the set of computers connected together.
The World-Wide Web (WWW) is a collection of documents (Web pages), which reference each other even through they are on different computers.
The URL (Uniform Resource Locator) is the address by which you specify a particular WWW page. A sample URL is http://www.cs.sunysb.edu/ skiena/101/cse101.html Note that it describes (1) a machine, (2) a file name, (3) an action (http).
A Browser is a program which reads WWW files, such as the Netscape Navigator.
HTML is the language which WWW pages are written in. Thus a browser must understand HTML and know how to display it on a screen.
Hypertext are documents which have extra links so you do not move through it linearly like a book. The WWW can be viewed as one giant hypertext document!