MyVar:
DC.L 0      ;reserves 4 bytes of storage. The label MyVar represents the address of the four 0 bytes shown here.

MyOtherVar:
DC.L $C0   ;reserves 8 bytes of storage. The first four bytes are initialized to 00 00 00 C0 and the second four to $00 $00 $01 $F4.
DC.L 500   ;MyOtherVar points to the first four bytes, you'll need pointer arithmetic to get to the second four.