The "mlp" could refer to a specific person's initials, a location, or another identifier not immediately obvious without opening the file.
It is highly likely to be a folder of image files (such as .jpg or .png) taken during a vacation, packed into a single file for easier downloading or sharing. fb-photo-vacation-mlp-07_10.rar
Likely a vacation album ("vacation") from a social media platform, possibly Facebook ("fb"), curated or shared around July 2010 ("07_10") [1]. The "mlp" could refer to a specific person's