Use for PCB All Layers

The work layer can be broadly divided into 7 categories: signal layers, internal planes (internal power/ ground layer), mechanical layer, solder mask layer, silk screen layer, others and system work layer.

1.Signal layers

It includes top layer, bottom layer, intermediate layer 1 and intermediate layer 2 …middle layer 30. The signal layer is used primarily for placement of components (top and bottom) and routing. The signal layer is positive. i.e. , at these operating layers.
The wires or other objects placed on the surface are areas covered with copper.

2.Internal planes (internal power/ ground layer)

Internal power / ground layer (referred to as inner layer) : internal plane, these levels of work are dedicated to the arrangement of power lines and ground wires. The lines or other objects placed at these levels are copper free regions. i.e., these layers are negative. Each internal power / ground can give an electrical network name, printed circuit board editor automatically the level and the other with the same network name (i.e., electrical connection pads), connected to the form of pre pull. Also allows the internal power / ground layer to be cut into multiple sub layers, that is , each internal power / ground layer may have two or more power supplies, such as +5 V and +15 V, and so forth.

3.Mechanical layer

The mechanical layer is generally used to place indicative information about the board and assembly methods, such as circuit boards, physical dimension lines, dimensional markings, data, through hole information, assembly instructions, etc…

4.Mask (solder mask, solder paste protection layer)

Solder resist: (top, bottom) (top solder barrier) and (bottom solder). The solder resist is negative and the pads or other objects placed on the layer are areas without copper.
Usually, in order to meet the requirements of manufacturing tolerances, the manufacturer often requires specifying a barrier extension rule to enlarge the solder resist layer. For different requirements of different pads, multiple riles can be set__ in the solder resist layer.
The solder paste protective layers are (top paste) (top layer solder paste protection layer) and (bottom paste) (bottom solder paste protection layer). The solder paste protection layer is similar to the solder resist layer, but when the hot re-follow (thermal convertion) technique is used to mount the SMD element, the solder paste protection layer is mainly used to establish the screen printing of the solder resist layer. The layer is also negative.
Similar to the solder resist, we can also enlarge or reduce the solder paste layer by specifying an extension rule. For different requirements of different pads,  multiple rules can also be set__ in the solder paste protection layer.

5.Silkscreen (screen printing layer)

(Top overlay) top screen printing layer and (bottom overlay) bottom screen printing layer. The screen printing layer is mainly used to draw the outline of components, the number of components placed, or other text information. When a PCB library element is placed on a printed circuit board, the number and outline of the element are automatically placed on the screen printing layer.

6.Others (other work layer)

In addition to the above work layer, there are the following work layers.
(keepout layer) inhibit wiring layer
The inhibit wiring layer is used to define the areas WHERE the components are placed. In general, we place line segments (track) and arcs on the forbidden wiring layer to form a closed area, allowing automatic routing of components within this closed area.
Note: If any part of the circuit or all circuitry is to be automatically configured or automatically wired, then a prohibited wiring area shall be defined on the inhibit wiring at least.
(Multilayer)
This layer represents all the signal layer, put on the components automatically in all layers of the signal, so we can pass multilayer, the pad or the through hole via quickly placed into the signal layer on all.
(Drill guide) drilling instructions
(Drilling drawing) borehole view
(Drill guide) drilling instructions and (Drilling drawing) borehole view, these two layers are mainly used to draw drill, hole drawings and location of boreholes.
(Drill guide) is mainly compatible with manual drilling and old circuit board manufacturing processes. For modern manufacturing process, more drill drawing is used to provide drilling references files.
We usually specify the drill hole information in the drill drawing work layer. When generating a drill file on a printout, a code diagram containing these drill holes information and which generates a drill hole position. It is usually used to produce a diagram of how to do circuit board processing.
Here’s is your attention:
Whether or not the (drill layer) working layer is set__ to a visible state, the drilling information generated automatically at the output is visible in the PCB document.
The drill drawing layer contains a special legend string, where the location of the string determines where the drill map information is generated when the printout is print.

7.System (system work layer)

DRC Errors layer
DRC Errors layer is used to display information that violates the design rules check. When the layer is in shutdown, the DRC error is not displayed on the workplace diagram, but the online design rule checking function will still work.
Connection layer
This layer is used to display electrical connections between components, pads, and vias, such as Broken Net Marker or Ratsnest, but the wire (Track) is not included in it. When the layer is turned off, these connections do not show up, but the program still analyzes its internal connections.
Pad holes (hole layer in the pad)
When the layer is opened, the inner hole of the pad is displayed on the diagram surface.
Via holes (through the inner hole layer)
When the layer is opened, an inner hole of the cross hole is displayed on the surface.
Visible grid 1
Visible grid 2
These two items are used to display raster lines.
At the same time, the functions of each layer are briefly described as below:
The top layer element layer, bottom layer wiring and plug-in components of the welding layer, the middle layer of midlayer, the layer is used for drawing wire or copper clad (and pad SMT patch device toplayer, bottom layer)