Did you know that 1/2=0? If you didn’t you could be in for some interesting surprises.
1/2 returns 0 because 1 and 2 are both integers. When you divide two integers you get back an integer. Now, we, as human beings, know that what you probably wanted was to get back 0.5. Unfortunately, computers really aren’t all that smart and we have to be very explicit with them.
Read on for more details, as well as a chart of which conversions may be implicit and which must be explicit.