A LIDAR (Light Detection and Ranging) survey – also known as a laser, laser scan or laser-sweep or point cloud survey use precise calibrated digital instruments such as laser scanners to accurately survey a site.
A laser scanner uses millions of individual laser measurements to build an accurate record of the areas and features to be surveyed, as demonstrated in this video.
This laser scan data is processed or ‘registered’ to create a 3D point cloud survey file from which 2D drawings or 3D models can be constructed.  The point cloud files can be both black and white or colour, depending on the project requirements.
They can also be issued in a number of different file formats (eg .rcs .rcp .E57) to be interoperable with your design software.
Measured building surveys are usually carried out using terrestrial laser scanners but may be supplemented with additional information obtained using traditional methods such as GPS, Total Station, Disto and photogrammetry.
While topographic surveys are usually undertaken using UAVs (drones) with supplementary information obtained using traditional methods such as GPS and Total Station.