Web-based training (WBT) is a type of training that is similar to CBT; however, it is delivered over the Internet using a web browser. Web-based training frequently includes interactive methods, such as bulletin boards, chat rooms, instant messaging, videoconferencing, and discussion threads. Web based training is usually a self-paced learning medium though some systems allow for online testing and evaluation at specific times.
(source Wikipedia)

It is a web-based version of formal learning, because there is a certain structure (in most cases) and sometimes even a virtual teacher; however, it contains elements of informal learning (learning by doing) and also elements of non-formal learning, in the respect that there is communication with other real-life people. The training aspect is also present.

1) constantly updated - new versions downloaded (bugs are eliminated)
2) can be improved and/or updated by those using it.
3) can be used by a team
4) can interact with others
5) could utilise other sources from the web simultanoeuosly eg. Leo, Wikipedia

1) security - can be hacked into
2) requires a stable internet access
3) can be difficult to concentrate on learning
4) the internet access in certain countries is limited or expensive

"complex skills"
languages
soft skills (teamwork, conflict solving etc)
job related skills, that are changing quickly

http://www.bellenglish.com/default.asp?
age range: teenagers to young adults, depending on the inidividual programe
features:
different gamelike excerices
problem-soving situations based on true-to-life settings
suitable for different levels of knowledge
forum and bulletin board
business telephone training
FCE Preperation
Chats
Links