Integers
Integers are whole numbers and are equivalent in range as your C compiler's long value. On many common machines, such as Intel Pentiums, that means a 32-bit signed integer with a range between -2,147,483,648 to +2,147,483,647. Integers can be written in decimal, hexadecimal (prefixed with 0x), and octal notation (prefixed with 0), and can include +/- signs.
Some examples of integers include
240000
0xABCD
007
-100
Note: As integers are signed, the right shift operator in PHP always does a signed shift.
Floating-Point Numbers
Floating-point numbers (also known as real numbers) represent real numbers and are equivalent to your platform C compiler's double data type. On common platforms, the data type size is 8 bytes and it has a range of approximately 2.2E-308 to 1.8E+308. Floating-point numbers include a decimal point and can include a +/- sign and an exponent value.
Examples of floating-point numbers include
3.14
+0.9e-2
-170000.5
54.6E42