Re: Can I tell my computer to do different tasks?

I believe you are asking about Speech Recognition programs (multi-tasking, 
which is how the question reads, is a whole different answer).  Today, 
there are a number of such programs available for the PC.  The major ones 
include Dragon System's and L&H Voice Express.  IBM has one, etc.

They all work the same way.  All [spoken] languages consist of "phonemes" 
(you might consider them "letters") which, when put together, form spoken 
words.  In English there are 42-44 (depending on what book you read) of 
them.  (Other languages have more or less of them).  The speech recognition 
program examines the input (from a microphone, usually), and acts like a 
spelling checker, looking up words in a "dictionary".  Like all spelling 
checkers, if it does not find a "word" it asks if that word should be added 
to the dictionary (this is the "learning" step in your program).  If it 
does find the word, it "builds" a command line based on "replacement 
values" for the "words" you supplied in the input.  When you are done, it 
passes them on to the command processor, as if you had typed them.

The task gets a little bit more complicated with the various Chinese 
dialects, because they also add in the concept of "tone".

The interesting work is not so much in the Phenome breakdown, and 
dictionary lookup, but rather in the filtering needed to "smooth out" the 
words so that different people may have their speech recgnized too, and at 
different speeds.  Also, just as Grammer Checkers are becoming better today 
(with checking syntax), Speech Recognition programs may improve by checking 
the synatax (and even the symantics!) of the spoken phrase.

Personally, I'd rather type, but then again, I keep away from GUI's too!