What is the difference between UCSD Pascal and the standard Pascal?

- The pack and unpack procedure of the UCSD Pascal system is not implemented and doesn’t have the packed keyword in it. Whereas, the procedure, is not, included in the standard Pascal.

- {} comments are included and implemented in a non-standard way. The example of a valid comment is as follows:
{hello world *)

- Whereas, this is not valid in UCSD Pascal and the comments are written using the nested brackets like:
{hello (* world *) of mine }

- The default field widths are not filled with the pre-defined numbers but they are having their minimum amount of space where the numbers can be printed.