It is supposed to make human's life easier - but at the same time, unfortunately, lazier.

If you choose to send email or instant message (such as MSN, Gtalk, Yahoo) rather than:

1) Walk to your colleague's cubical and discuss
2) Give a ring to the person and discuss the matter

Then here are few things you may wanna know:

1) Text messaging is one of the worst way of communication (it often leads to wrong assumption)
2) It is also a rather passive way of communication (send and wait for response?)
3) If you could talk face to face (or at least, on the phone), the message will be much clearer and you can correct each other on the spot if there's any mistake
4) If you could talk face to face, you can even illustrate the issue/matter on the spot (into diagram etc, you name it)- an even powerful way of communication
5) Text messaging is simply - slow. Just look at the process -
i) You understand/visualise the things
ii) You convert it into text
iii) You send out the message
iv) You wait for the person to respond
v) The person sees the message
vi) The person tries to visualise the text
vii) Making assumption that what he/she visualise is the same as you do
viii) Respond on your message
ix) If you find that it's incorrect, you'll make a modified version of your text, and start from step iii again.

So, my point is, email or text messaging is cheap and fast (i.e. you don't have to meet up physically, which takes time on traveling) but

Email should be used for communicating the summary of the conversation, especially in work (or at least, when there's a consensus) - if you want to seek for a lot of clarification, hold a meeting instead

Text messaging - should be used less for discussing serious matter. It's better used as soft reminder/alert.

It's all about efficiency - you don't waste my time and I don't waste yours - cos we've got better things to do in life or work.