Web Development 1
Dr Derek Bridge
School of Computer Science & Information Technology
University College Cork
Administrivia: The lecturer
Administrivia: Module delivery
||5 credit module
||2 × 1 hr per week
||1 × 2 hr per week
||At least 2 hrs per week
|Course web site:
Contains copies of some of the slides
N.B. Slides, not notes!
||1.5 hr written exam (75% of the marks)
||Web site project (25% of the marks)
|How to fail:
||Skip lectures & labs; avoid private study; cram the night before the exam; expect the exam to be a memory test
|How to pass:
||Attend lectures & labs; take notes; organize your notes; tackle the lab activities properly; expect a problem-solving exam
- Plagiarism is presenting someone else’s work as your own. It is a violation of
UCC Policy and there are strict and severe penalties.
- You must read and comply with the UCC Policy on Plagiarism
- The Policy applies to all work submitted, including software.
- You can expect that your work will be checked for evidence of plagiarism or
- In some circumstances it may be acceptable to reuse a small amount of work by
others, but only if you provide explicit acknowledgement and justification.
- If in doubt ask your module lecturer prior to submission. Better safe than sorry!
The risk of complacency
Ancient Chinese Proverb
You can't learn something if you think you already know it.
What the web was for — originally
Servers and clients
- Web client computers
- run web client software (e.g. browsers)
- the software make requests for web resources (e.g. HTML files, CSS files, image files, videos, programs, …)
- Web server computers
- host web resources (e.g. HTML files, CSS files, image files, videos, programs, …)
- run web server software that responds to requests
Web requests and responses
- Knock, knock
- Who's there?
- Dwayne who?
- Dwayne the pool, I'm dwowning
- If two computers are to exchange messages, we need to specify
and agree the rules of communication
- In computer networking, such a set of rules is called a communications protocol
- HTTP - HyperText Transfer Protocol
- The protocol used for web requests and responses
- The protocol is defined by the Internet Engineering Task Force (IETF)
HTTP response status codes
- 1XX: Informational:
- e.g. 100 Continue
- 2XX: Success:
- e.g. 200 OK, 206 Partial Content
- 3XX: Redirection:
- e.g. 301 Moved Permanently
- 4XX: Client error:
- e.g. 400 Bad Request, 403 Forbidden, 404 Not Found
- 5XX: Server error:
- e.g. 500 Internal Server Error, 503 Service Unavailable
- Web resources must also comply with rules - otherwise browsers won't know what to do with them
- The World Wide Web Consortium (W3C) is responsible for specifying, e.g.,
- HTML, the HyperText Markup Language
- CSS, Cascading StyleSheets
- Other organizations specify other types of resource (images, video, audio, server-side programming languages, client-side programming languages, …)