Until quite recently all phototrichogram analysis was done manually. Photographs on the first day and five days later would be taken and compared side by side. A Trichologist or technician would literally take a ruler and measure the length of the hair fibers and their diameter, write all the measurements down by hand, and then calculate the average hair growth rates and so on. While this technique provides a lot of accurate data, it is very time consuming and, therefore, expensive. As a result, the phototrichogram has not been commonly available. With an introduction of digital trichoscopy with based on it diagnostic approach, including a computerized and fully automated phototrichogram system to define hair growth, that can be quickly applied, has changed the entire situation. The principle of digital phototrichogram is the same as for the original phototrichogram. A small spot on the scalp should be selected and used for analysis. For a differential diagnosis between inherited and diffuse hair loss, digital phototrichorgam is typically performed in 2 separate areas - the frontal-parietal and occipital. Furthemore, to evaluate the dynamics of potential treatment by phototrichogram, it makes sense to use areas of most pronounced hair thinning. For example, frontal, parietal, occipital and temporal areas, which typically tend to be variously affected and progressing quite differently in terms of hair distribution in cases of inherited hair loss, may be evaluated and monitored more closely. In selected areas, roughly 10mm in diameter, all hairs are trimmed down to a certain minimal length, usually by 1mm, with a special trimmer and an image is taken to determine whether all hairs in the field of view are trimmed to identical length, but this time with a digital close-up trichoscope, typically under x30 to x60 magnification. Normally in 48 to 72 hours, when newly grown (from initial 1mm) length Anagen hairs can be located between the remaining length former size Telogen hairs, all hairs are being dyed by means of a special hair dye in order not to make them most noticeable and contrasted from scalp in order not to miss even the tiniest gray or discolored hairs, and an image of the same spot is being taken again after a viscous immersion oil applied on it in order for entire hairs lengths to be fully visible. This image is then examined by a software system, allowing to measure each individual hair fiber. Once the complete assessment is performed, the software can calculate how many hairs are growing, not growing, missing or appear to be newly grown, therefore, establish Anagen/Telogen hairs ratios, estimate their growth and shedding rates, as well as calculate hair density and diameters in the premeasured area. Also, nowadays, similar to "classic phototrichogram" and clinical research studies, especially testing new hair loss treatments, an additional step is being taken by most Trichologists, as well. Patients, similar to study participants, would have a dot "tattooed" on their scalp in these shaved areas. Although, with digital microscopic technology now utilized, while the regular tattoo paint used, it is being applied by means of a syringe with insulin needle, creating a tiny dot on the scalp, unnoticeable by bare eye and, thus, not uncomfortable to participants. It allows Trichologists to come back to exactly same spot after several months or even years to do another phototrichogram evaluation. This way, Trichologists can produce a detailed quantitative evaluation of hair growing environment in exactly the same spot on the scalp in a longitudinal study period and build up a good understanding of long-term treatment effects on hair. By now such "tattooing" became almost a standard attribute of any digital phototrichogram testing, performed by Trichologists on any patients due to the same reasons. To get a better understanding of these specialty techniques, this detailed description with video presentation shall be quite helpful.