What is the difference between the dot line and single line and double line in the Grasshopper file?

When the Fancy Wires option is enabled in the Grasshopper View menu, then the wire display tells you something about the data that flows through them. There are 4 different wire display types:

  1. Single orange wire: no data is transferred, the parameter on the left end is empty.

  2. Single grey wire: a single data item is transferred.

  3. Double grey wire: a list of data items is transferred.

  4. Double dashed grey wire: multiple lists of data items are transferred.

~David Rutten