OllyDbg is a 32-bit code level debugger for Microsoft(R) Windows(R). Emphasis on binary code analysis makes it particularly useful in cases where source is unavailable. It recognizes procedures, API calls, switches, tables, constants and strings, locates routines from object files and libraries, allows custom labels and comments in disassembled text, writes patches back to executable file and much more. No installation, no trash in registry and system directories. You can even start OllyDbg from the floppy disk. New features in version 1.01 include improved analysis, extended user interface and support for debugging information in Borland(R) format.