Long variables are extended size variables for number storage, and store 32 bits (4 bytes), from -2,147,483,648 to 2,147,483,647.
If doing math with integers, at least one of the numbers must be followed by an L, forcing it to be a long. See the Integer Constants page for details.
long speedOfLight = 186000L;
// see the Integer Constants page for explanation of the 'L'
long var = val;
var – the long variable name
val – the value you assign to that variable
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