Lord Shiva is worshipped during this entire month.  Mondays of this month are dedicated to the worship of Lord Shiva and Tuesdays are dedicated to Parvati Maa.  Devotees fast on either of these days as ‘Shravan Somvar Vrat’ or ‘Mangal Gauri Vrat’. As described in our sacred texts, Samudra Manthan (churning of the cosmic ocean) was done during this month.  A large number of valuable gifts came out of the ocean when it was churned. However, the ocean also gave up halaahal, a poison that was so powerful that it could destroy everything. Lord Shiva, in his infinite kindness, drank this poison and stored it in his throat.  This turned his neck blue, thus giving him the name Neelkanth.  As Lord Shiva saved everyone during this month, devotees of Lord Shiva offer Him their prayers during this time.