Valid Perl numbers include whole numbers, floating point numbers,
and numbers in scientific notation.
Internally to Perl, all scalar numbers are stored as double
precision floating point values (as it is defined by your operating
system).
Example Scalar Numbers (shown as float and integer literals):
1 # one
1.2 # one and two tenths
6.02e-23 # Avagadros number (6.02 times 10 to the -23 power
1.0E6 # One million
-5.3 # Negative 5 and 3 tenths
1234567.890 # Just what it appears
If you have a hard TTd floating point number, it is called a
float literal.
If you have a hard TTd integer number, it is called an
integer literal.
Perl also allows octal representation of literals (only)
by use of a leading zero. For example, 010 is octal 10
(the decimal value of 8).
Perl also allows hexadecimal representation of literals
(only) by use of a leading zero x. For example, -0xff
would be negative 255 decimal.
This should look remarkably familiar to you C programmers. You will find a great deal in common with C and Perl.