When you create a work order from the Asset grid of an existing work order, the category and selected assets will be carried over into the new work order. The two work orders will then be linked in the Related Work Orders grid (in the Related tab in the Standard Work Order module). This is useful if you have several assets that need additional work done outside of the current work order.
For example, if you have a TV inspection work order involving 20 sewer pipes and 5 of those pipes need to cleaned, you can create another work order from the Asset grid and the category and the 5 pipes you selected in the Assets grid will be carried over to the new work order.
How To Create a New Work Order from the Assets Grid