Main purpose? Now bitcoin is used mainly in gambling and porn. (more than 60% of transactions)
Benefits of bitcoin? Quick, cheap and irreversible transactions.
Gambling of course yes but porn
care about giving us the source which says that over 60% of the transactions involve gambling (i agree) but porn. I think bitcoin transactions also includes personal trades, exchanges, buying goods or services, donations,trading and much more try exploring a bit more
Also op quite a c.b.s.e. format you are using for the question, it doesn't need to be that formal.
"tell me the properties and characteristics of bitcoin.'
isn't it???