CC3+ contains a huge amount of various commands and features. This series highlights a number of these. There won't be any special progression to this series, and the command will be selected from the entire range, from the simple basic commands, to more advanced features intended for the more advanced users. Feel free to use this topic to discuss the command presented.
This series is called the command of the week, but it could also explain a feature. The explanations will tend to explain the technical parts of the command, and is intended to highlight the basics (and complexities) of the command, and information about how to use it, but won't be a detailed tutorial. It is up to you to use it creatively in your maps.

Week 7 - Measuring Tools

CC3+ has several tools that can be used to measure things in your map. These are great to use to make sure things are the correct size in your map, to get a bit of perspective on things, or to use during a game session, for example to figure out how far the characters will need to travel if they follow that windy road or river. As a game master, I always use the .fcw at the table instead of an exported image to be able to measure such things.

Where to find it?

Menu: Info Menu -> Bearing, Distance, Length Along and Area
Command Line: BEARING, DISTANCE, LENGTH, AREA

How to use it?

These commands are relatively easy to use, but keep in mind that the values they provide will be in map units. As you already know, the definition of a map unit depends on the map, and are typically miles/km for overland maps and feet/meters for city and floorplan maps. It is therefore important to know what units this map is scaled in when using these commands for the answer to make sense. Pay particular attention if you compare features across multiple maps, in case some of them are in metric while others are in imperial units.

When using these commands, keep in mind the various modifiers, such as endpoint, midpoint and intersection, as well as snap. The modifiers are really helpful when you wish to do precise measurements.

Bearing

This command gives you the direction of a line, in the exact point you used to select it. For a straight line, it doesn't matter where you click on it, as the whole line goes in the same direction, but for a curved line, like an arc or a smooth path, the direction it is pointing will change all along it's length. So make sure you select it at the exact point you wish to measure (modifiers may be of help here). When you first start this command, the command line will read 'Bearing From'. You'll notice that your cursor is both a crosshair and that you have the pick cursor box. As long as you use the pick cursor box to pick an entity, you will select that, and the command will end, giving you the bearing of that entity. If you click outside of an entity, you will instead set a starting point, and will then be asked for an ending point. Once you click anywhere, CC3+ will give you the bearing between the two points clicked.
When selecting an entity, the command gives you the bearing according to the direction the entity is poiting, from the starting point towards the ending point. This means that two identical lines may give results that are 180 degrees different from each other if one were drawn from left to right, while the other was drawn from right to left. In other words, the original placement of the nodes matter.

Distance

Distance simply have you click two points and gives you the distance between them, it doesn't care anything about entities. If you wish to measure between entities or specific points on entities, use the various modifiers to precisely place the starting and ending points for this command.

Length Along

I find this command particularly useful, because it can measure length along a curved (or fractalized) entity. I use this command a lot in my games to measure the length of roads my players travel.
The command fill first ask you to select the entity to measure along. Once you have picked an entity, it will ask for the starting point. For this, you can click anywhere in your drawing, and CC3+ will use the point on the entity that is closest to the point you clicked as a starting point. I recommend clicking as close as possible to the actual starting point to make sure it is where you expect it to be (and you can use things like modifiers to pick this with perfect precision if needed). CC3+ will then ask for an ending point, the same notes about the selection apply here. The length measured will be along the entity, and NOT just a straight line between the points.
Additionally, instead of picking the starting point, you can also simply click the right mouse button to get the length of the entire entity.

Area

When working with a map, it can sometimes be difficult to get the proper perspectives on the size of your landmasses. I find that the area command is really helpful here. Area measures the area covered by any polygon. I find that by measuring the area of a landmass, and then look up the sizes of real-world islands or continents help me put the size of the landmass into perspective. It is also great when explaining the size of something to your players. A scale bar is great, but it doesn't provide the same perspective as a comparison with real life places do. Looking up other maps in the same scale (Google maps is great because it is zoomable with dynamically changing detail) allows me to figure out how much detail this map should have, for example by paying attention to how many cities show up in that view and the general size of them.
When starting this command, CC3+ will ask you to click points to define the area (right click when done), or to hit Enter to select an entity instead. Normally, I will always to the latter, and then select an entity in my map, like a landmass to get the size of it.