So this is Socks.
He’s a milk chocolate brown colored unicorn that has a blonde mane and tail with mis-matched socks on each leg, thus his name.
He’s nopony important and works as an armorer for the Canterlot guards, crafting armor and weapons for them, thus his forge hammer cutiemark.
His sister and mother went to Ponyville’s only Carousel Boutique, and got him a surprise. They bought Socks some socks :P And he’s quite unsure about wearing them…