Self-explanatory brand name for a product or service that deals with photography / pictography.
The name "pics" has only four characters and just one syllable. One-syllable names are highly rare and very valuable. One syllable names are used by established brands like Square, Nike and Shell.
Pics.co is a dot-co domain. Dot co domains are a popular top level domain (TLD), like dot com, or dot net. CO is the acronym for "company" or "corporation".
This domain was first registered in September 2010. Older domains have an advantage when ranking in search engines.