Are "nil" and "null" interchangeable?

Solution 1:

NULL is used in computing most often (always?) to signify "not a value." This is different than zero: in a bank database, a zero value means no money, while a NULL value means there has been no value assigned to the balance.

This is a specialized usage, but increasingly common as more people learn to program.

Solution 2:

Almost the only time you hear or see null is in the legal expression ‘null and void’, while nil normally indicates that a football team has scored no goals. If the bottom line of your bank statement shows neither a credit nor a debit, what you have is a zero balance.

Solution 3:

Null is also used in mathematics (a null set) and science (null hypothesis). I can't think of a time when nil is used in those areas.

Etymologically, null is from French, and nil is from Latin.