Software Engineering for Internet Applications - Student Community

UDDIUnixcustomer's credit card. If the credit card can't be billed, youwant to make sure that the order doesn't get shipped. If theshipping database can't accept the order, you want to makesure that the credit card doesn't get billed. RDBMSes suchas Oracle provide significant support for implementingtransactions.Universal Description, Discovery, and Integration. Like aworldwide Yellow Pages, this is an XML-based registrywhere companies can list the Web services they provide.More: uddi.org.An operating system developed by Ken Thompson andDennis Ritchie at Bell Laboratories in 1969, vaguely inspiredby the advanced MULTICS system built by MIT. Unix reallytook off after 1979, when Bill Joy at UC Berkeley released aversion for Digital's VAX minicomputer. Unix fragmented intoa bewildering variety of mutually incompatible versions, thusenabling Microsoft Windows to take over most of the servermarket. The only surviving variants of Unix are Sun's Solarisand Linux.URLUniform Resource Locator, also Uniform Resource Identifier(URI). A way of specifying the location of something on theInternet, e.g., "http://photo.net/wtr/thebook/glossary.html" isthe URL for this glossary. The part before the colonspecifies the protocol (HTTP). Legal alternatives includeencrypted protocols such as HTTPS and legacy protocolssuch as FTP, news, gopher, etc. The part after the "//" is theserver hostname ("photo.net"). The part after the next "/" isthe name of the file on the remote server. Also see "AbstractURL". More: http://www.w3.org/Addressing/.USENETA threaded discussion system that today connects millionsof users from around the Internet into newsgroups such asrec.photo.equipment.35mm. The original system was built inthe late 1970s and ran on one of the wide-area computernetworks later subsumed into the Internet.Version Control SystemA system for keeping tracking of multiple versions of a file,usually source code. Version control systems are mostuseful when many developers are working together on aproject, to help prevent one developer from overwritinganother developer's changes, and to make it easy to revertto a previous version of a file. An excellent open-sourceSuppose you want something more expressive. You want the wordreally to be in italic type:My Samoyed is really hairy.HTML stands for Hypertext Markup Language. The is markup. Ittells the browser to start rendering words in italics. The closesthe element and stops the italics. If you want to be more tasteful,you can tell the browser to emphasize the word really:My Samoyed is really hairy.Most browsers use italics to emphasize, but some use boldface andbrowsers for ancient ASCII terminals (e.g., Lynx) have to ignore thistag or come up with a clever rendering method. A picky user with theright browser program can even customize the rendering of particulartags.There are a few dozen more tags in HTML. You can learn them bychoosing View Source from your Web browser when visiting siteswhose formatting you admire. You can look at the HTML referencechapter of this book. You can learn them by visitinghttp://dir.yahoo.com/Computers_and_Internet/Data_Formats/HTML/Guides_and_Tutorials/ and clicking through to one of thecomprehensive online HTML guides. Or you can buy HTML &XHTML: The Definitive Guide (Musciano and Kennedy; O'Reilly,2002).Document StructureArmed with a big pile of tags, you can start strewing them amongyour words more or less at random. Though browsers are extremelyforgiving of technically illegal markup, it is useful to know that anHTML document officially consists of two pieces: the head and thebody. The head contains information about the document as a whole,such as the title. The body contains information to be displayed bythe user's browser.Another structure issue is that you should try to make sure that youclose every element that you open. If your document has a it should have a at the end. If you start an HTML table witha and don't have a , a browser may displaynothing. Tags can overlap, but you should close the most recentlyopened before the rest, e.g., for something both boldface and italic:32623