Lines Parallel

 Lines parallel 

Acral nevus 

Melanoma 

Parallel furrow -  Benign 

Parallel ridge -  Melanoma, Haemorrhage

Hemorrhage Talon Noire Parallel ridge but pared clean with blade

While it is worth noting that Parallel ridge patterns are a dermoscopic sign of melanoma it can be seen in the following benign conditions: 

 Subcorneal hemorrhage or Talon Noir 

Ethnic pigmentation 

Playstation finger 

Self tanning lotion 

Haemangioma