Since macOS 15 Sequoia the Mac tiles windows on its own, in two ways:
- Drag a window to the left or right edge and it fills that half; to the top for full size; into a corner for a quarter. Hold ⌥ while dragging to see the zones earlier.
- Keyboard: fn⌃← and fn⌃→ for halves, fn⌃F to fill the screen, fn⌃R to put the window back. Hovering the green button shows the same options as a menu.
What a Windows user misses: the shortcuts do not chain (pressing left twice does not move the window to the other half), there is no Snap Assist offering the other windows for the empty side, tiled windows keep a margin around them, and macOS 14 Sonoma has none of this at all. Quarters and thirds exist in the green-button menu but not on the keyboard.
The margins can be switched off under System Settings → Desktop & Dock → "Tiled windows have margins". Everything else needs a window tool.