Open-Source Software:

Source code is freely available for anyone to view, modify, and distribute.

Generally free to use and modify.

Community-driven development.

Examples: Linux, Mozilla Firefox.

Shareware:

Initially free but with limitations or trial versions.

Requires payment for full features or to remove limitations.

Examples: WinRAR, trial versions of commercial software.

Freeware:

Completely free to use.

Provides full functionality without payment.

Examples: VLC media player, free web browsers.