What is Inno Setup?

Inno Setup version 6.2.2
Copyright © 1997-2023 Jordan Russell. All rights reserved.
Portions Copyright © 2000-2023 Martijn Laan. All rights reserved.
Inno Setup home page [external link]

Inno Setup is a free installer for Windows programs by Jordan Russell and Martijn Laan. First introduced in 1997, Inno Setup today rivals and even surpasses many commercial installers in feature set and stability.

Key features:

Is it really free of charge, even for commercial use?

Yes, it may be used completely free of charge, even when deploying commercial applications.

(Note: "Completely free of charge" must not be confused with "completely free". Inno Setup is copyrighted software, not public domain software. There are some restrictions on distribution and use; see the LICENSE.TXT file for details.)