long term debt is given for a long period of time generally 
for more than 5 years whereas short term debt is concerned 
with the debt less than 5 years

A debt whic are payable after one year considered as Long 
term debts.On other hand debt which are paybale within a 
year called short-term debt.ther is one more duration 
between 3 to 5 years is called Middle term debt.

The debt which we need to pay within one year is short term
debt where as long term debt is we need to pay more than one
year

The difference between long term debt and short term debt is
that
Long term debt is a debt that can be paid after a one year
and short term debt is a debt that has to be paid with in a
period of one year