Usage:

Align:

Aligning has two methods: Origin and Bounding Box.

When you set the method to 'Bounding Box' more options become available.(See Gif Below)

Select the Axis on which you want to align the objects.

Use the lower-left panel to add or remove more axis or to change any other parameter.

Distribute:

Objects can be distributed into 1 Dimension (Linear) or 2 Dimensions (Grid)

1D:

1 Dimension distribution also has two methods: Origin and Bounding Box. And similar to Align when you use the Bounding Box method more options become available.

Select the Axis along which you want to distribute the selected objects.

Objects will be distributed between the first and the last object along that axis.

Equal Distance vs Equal Gap:

2D:

Set the Grid Size(Number of Cells) and Cell Size

Select the placement of the Grid with respect to the Active Object using the Right/Left and Up/Down options.

And then select the plane of distribution to distribute the objects in a grid.

See Gif Below.

Other Features:

Randomize:

Randomize the location of selected objects in specified Axes.

Swap Location:

Swap the location of 2 selected objects.