From the manual:
"THINK's Lightspeed Pascal is a unique development environment for the
Macintosh. It features a very fast compiler, a faster linker, an
integrated text editor designed specifically for Pascal syntax, an
auto-make facility, advanced debugging tools, and a project organizer
that holds all the pieces together. Because the editor, the compiler,
and the linker are all components of the same application, THINK
Pascal knows when edited source files need to be recompiled... With
THINK Pascal you can build Macintosh applications, desk accessories,
device drivers, and any kind of code resource..."

DL#1 is an installed folder copy of v2.0 and an updater to v2.03 that
makes some bug fixes
DL#2 provides disk images of the two original 800k floppies for v2.0,
which include several files/resources that are not in DL#1 (incl.
Release notes, ResEdit v1.2d1, RMaker, MacsBug, Compare, and the
Projects and Profiler folders)

See also:
[THINK LS Pascal v1.x][1]
[THINK Pascal v4.0 with PDF manuals][2]
[THINK Pascal 4.5][3]

Compatibility
Architecture: 68k

Requires at least System Tools 5.0 (System 4.2/Finder 6.0).
Recommended for System 6.0 on the MacPlus, SE, and Mac II and will run
on Mac 512Ke with at least 1Mb of RAM.

  [1]: http://macintoshgarden.org/apps/think-lightspeed-pascal-10
  [2]: http://macintoshgarden.org/apps/symantec-think-pascal-40
  [3]: http://macintoshgarden.org/apps/think-pascal-45