Jenis-jenis Virus Komputer

� Virus boot-sector: menggantikan atau memasukkan dirinya ke dalam 
boot-sector--sebuah area pada hard drive (atau jenis disk lainnya) 
yang akan diakses pertama kali saat komputer dinyalakan. Virus jenis 
ini dapat menghalangi komputer Anda untuk melakukan booting dari 
hard disk. 

� Virus file: menginfeksi aplikasi. Virus ini melakukan eksekusi 
untuk menyebarkan dirinya pada aplikasi dan dokumen yang terkait 
dengannya saat file yang terinfeksi dibuka atau dijalankan. 

� Virus makr ditulis dengan menggunakan bahasa pemrograman makro 
yang disederhanakan, dan menginfeksi aplikasi Microsoft Office, 
seperti Word dan Excel, dan saat ini diperkirakan 75 persen dari 
jenis virus ini telah tersebar di dunia. Sebuah dokumen yang 
terinfeksi oleh virus makro secara umum akan memodifikasi perintah 
yang telah ada dan banyak digunakan (seperti perintah "Save") untuk 
memicu penyebaran dirinya saat perintah tersebut dijalankan. 

� Virus multipartite: menginfeksi baik file dan boot-sector--sebuah 
penjahat berkedok ganda yang dapat menginfeksikan sistem Anda terus 
menerus sebelum ditangkap oleh scanner antivirus. 

� Virus polymorphic: akan mengubah kode dirinya saat dilewatkan pada 
mesin yang berbeda; secara teoritis virus jenis ini lebih susah 
untuk dapat dideteksi oleh scanner antivirus, tetapi dalam 
kenyataannya virus jenis ini tidak ditulis dengan baik, sehingga 
mudah untuk diketahui keberadaannya. 

� Virus stealth: menyembunyikan dirinya dengan membuat file yang 
terinfeksi tampak tidak terinfeksi, tetapi virus jenis ini jarang 
mampu menghadapi scanner antivirus terbaru. 

How to Connect Your Computer to Your TV

There's something painfully ironic about sitting on your living room couch, just a few feet away from a beautiful widescreen HDTV, watching a movie on your tiny laptop. Yet this is what most of us do when we download movies or TV shows onto our computers.

The same goes for showing off our latest digital photos to friends. We all huddle around the 15-inch computer display while the TV screen goes unused. And what about that PowerPoint presentation you just gave at work? Wouldn't it have looked 1,000 times better on the wall-mounted plasma display in the conference room?

There are many compelling reasons why we want to connect our computers to our televisions, especially now that HDTVs are so popular. Everything from movies to photos to work presentations were made for the big-screen experience.

The first personal computers used TVs for monitors, but computer graphics technology quickly outpaced the image quality on standard-definition TVs (SDTVs). The typical modern computer monitor has the ability to display images at a much higher resolution than a regular TV. A computer monitor can display more individual pixels than an SDTV.

Even today, hooking a computer to an SDTV only makes sense if you want to use your computer as a DVD player. If you try to use an SDTV as a monitor, you'll have a hard time getting your full desktop to fit on the screen.

But with the advent of high-resolution, high-definition TVs like flat-panel LCDs, plasma, LCoS, and DLPdisplays, televisions now make excellent computer monitors. In fact, that's what the manufacturers of PC-based media centers are trying to achieve. The tricky part is figuring out exactly which TVs work with which computers and how to connect them all together.

CIRI-CIRI MAKLUMAT YANG BAIK UNTUK KEGUNAAN PENGGUNA

 Tepat

Maklumat yang dihasilkan bebas daripada ralat. Maklumat yang mengandungi ralat  adakalanya lebih merbahaya daripada keadaan tiada maklumat. Ini kerana maklumat sedemikian mungkin membuatkan pengguna mengambil keputusan yang salah

Lengkap

Maklumat sempurna dan lengkap bermaksud segala keperluan  pengguna   maklumat dipenuhi

  Berwibawa

Maklumat tersebut mempunyai kebolehpercayaan yang tinggi disamping  boleh dirujuk semula akan sumber maklumat tersebut sekiranya dikehendaki.

  Relevan

Maklumat yang dapat memenuhi kehendak dan kemahuan pengguna maklumat.

 Jimat

Maklumat yang akan dihasilkan oleh sistem maklumat tersebut mestilah  mempunyai ciri keberkesanan kos, dimana pelaburan bagi menghasilkan maklumat tersebut adalah rendah berbanding pendapatan ataupun keuntungan yang diperolehi.

  Anjal

Maklumat yang dihasilkan boleh digunakan oleh orang ramai  (pengguna) dan untuk pelbagai tujuan.

Ringkas

Maklumat yang dipersembahkan kepada pengguna hendaklah dalam bentuk yang mudah difahami.  Maklumat yang terlalu padat atau terlalu banyak boleh menyebabkan limpahan maklumat kepada pengguna.  

Pemasaan (Timely)

Ciri ini sangat penting kerana maklumat di luar masa dikehendaki, mungkin tidak lagi berguna.  Apabila pengguna maklumat memerlukan suatu maklumat pada suatu masa dan tempat, maka sistem maklumat tersebut seharusnya berkeupayaan untuk menjanakan maklumat tersebut tepat pada waktunya.  

 Keselamatan

Maklumat seharusnya mempunyai ciri sekuriti bagi membolehkan hanya orang yang berhak dan layak sahaja memilikinya.

What is e-commerce

 Transacting or facilitating business on the Internet is called ecommerce. Ecommerce is short for "electronic commerce."

Popular examples of ecommerce revolve around buying and selling online. But the ecommerce universe contains other types of activities as well. Any form of business transaction conducted electronically is ecommerce.

Examples of Ecommerce

• Online Shopping
  Buying and selling goods on the Internet is one of the most popular examples of ecommerce. Sellers create storefronts that are the online equivalents of retail outlets. Buyers browse and purchase products with mouse clicks. Though Amazon.com is not the pioneer of online shopping, it is arguably the most famous online shopping destination.
  
• Electronic Payments
  When you are buying goods online, there needs to be a mechanism to pay online too. That is where payment processors and payment gateways come into the picture.
  
  Electronic payments reduce the inefficiency associated with writing and mailing checks. It also does away with many of the safety issues that arise due to payment made in currency notes.
  
• Online Auctions
  When you think online auction, you think eBay. Physical auctions predate online auctions, but the Internet made auctions accessible to a large number of buyers and sellers. Online auctions are an efficient mechanism for price discovery. Many buyers find the auction shopping mechanism much interesting than regular storefront shopping.
  
• Internet Banking
  Today it is possible for you to perform the entire gamut of banking operations without visiting a physical bank branch. Interfacing of websites with bank accounts, and by extension credit cards, was the biggest driver of ecommerce.
  
• Online Ticketing
  Air tickets, movie tickets, train tickets, play tickets, tickets to sporting events, and just about any kind of tickets can be booked online. Online ticketing does away with the need to queue up at ticket counters.

Types of Ecommerce
Ecommerce can be classified based on the type of participants in the transaction:

• Business to Business (B2B)
  B2B ecommerce transactions are those where both the transacting parties are businesses, e.g., manufacturers, traders, retailers and the like.
  
• Business to Consumer (B2C)
  When businesses sell electronically to end-consumers, it is called B2C ecommerce.
  
• Consumer to Consumer (C2C)
  Some of the earliest transactions in the global economic system involved barter -- a type of C2C transaction. But C2C transactions were virtually non-existent in recent times until the advent of ecommerce. Auction sites are a good example of C2C ecommerce.