Grid is described as 'The fast, easy way to organize windows on your Mac. Snap windows by using gestures, keyboard shortcuts, dragging to corners, or menu bar. - Works with macOS 10.15 Catalina. OS X 10.10 and higher' and is an app in the OS & Utilities category. There are more than 50 alternatives to Grid for a variety of platforms, including Mac, Windows, Linux, Android and PortableApps.com. The best alternative is AquaSnap, which is free. Other great apps like Grid are Rectangle (Free, Open Source), WindowGrid (Free), BetterTouchTool (Paid) and altdrag (Free, Open Source).
BetterSnapTool is a utility that mimics Windows 7 Aero snap, allowing you to easily manage your window positions and sizes by either dragging them to one of your screens corners or to the top, left or right side of your screen.
Amethyst is a tiling window manager for Mac similar to the xmonad tiling window manager popular on Linux. Amethyst is written in Objective-C and has configurable shortcuts, multi-monitor support, multiple layouts, and the option to float certain applications.
HyperDock adds Windows 7 like features and more to Mac OS X. Select individual application windows & tabs just by moving the mouse on a dock item, use mouse clicks to quickly open new windows and many more.
KDE Mover-Sizer is a lightweight program enabling KDE-style alt-click moving and resizing for Windows XP, 7, 2000, 2003, Windows Server, and Vista. It is a background application that emulates the behaviour of KDE, which is a rather good Linux desktop environment.