This menu is used to give contextual orders to the ships you currently have selected, it works in all view modes (sector map, ship view, galactic map). To do so, select one or several of your ships, and this small panel will appear on the bottom left of the screen:
1st button is the move order. Click it, right click on the destination and your ship(s) will move there. If you right click on a ship or station, your selected ship(s) will protect said object.
2nd button is the attack order. It works the same way. If you right click an empty space, you'll issue an attack/move order, meaning that your ships will move toward that position attacking any hostile in sight. If you targeted an object you'll order your ships to attack this object.
3rd button is used to order them to patrol a sector. Here again, your mouse cursor will change, right click the sector you want your ships to patrol and they will do so.
4th button is for dock builders and will open the station building menu. It is detailed below.
5th button will order your ship to seek repairs at a friendly dock. It doesn't need a right click. If you are a faction it will look for one of your nearby facilities with a repair bay. If not, it will go to the nearest friendly station.
6th button will order your ships to collect all loot in the current sector.
7th button will order your ships to dock at a specific location.
The last button will cancel current orders.
The dock building button is enabled only if you have a Dock Builder class ship selected. The station will be built where the ships is currently located. Clicking the button will open the menu displayed in the above screenshot. You need money in your station building account to build one of those. Also, sectors can only support a given amount of stations of each type. The Sector Info panel can tell you what can and what cannot be built in a specific sector.