Pelles C is a lightweight freeware integrated development environment for Windows and Pocket PC programming in the C language.
Pelles C is a complete development kit for Windows (and Windows Mobile, but this platform is fading away). It contains among other things an optimizing C compiler, a macro assembler, a linker, a resource compiler, a message compiler, a code signing utility, a make utility and an install builder.
It also contains an integrated development environment (IDE) with project management, debugger, profiler, source code editor, and resource editors for dialogs, menus, string tables, accelerator tables, bitmaps, icons, cursors, animated cursors, animation videos (AVI's without sound), versions and XP manifests.
The compiler is originally based on LCC (by Chris Fraser and David Hanson), but since then enhanced with support for C99 and C11, a global optimizer, a new register allocator, a function inliner, intrinsic functions, and many Microsoft C extensions.
The install builder for Windows is originally based on NSIS from Nullsoft.
Reference: The Official Website