Anchor bolts are what secures the wood part of the cottage to the concrete part - the wood framed walls to the concrete walls. I illustrated the anchor bolts in a previous post, (Anchor Bolts... Holding the Cottage down!), and promised an explanation.
The diagram at right illustrates the parts of this system. The anchor blot is set in the concrete before it hardens with its threaded part exposed. When a wall is framed, holes corresponding to the locations of the anchor bolts are drilled in the sill or bottom plate of the wall before it is raised. (see... Framing, the 1st Wall on the 1st Floor and 4 Steps to Rasing a Wall: Square, Prepare, Lift, Level and Brace)
The wall is raided onto the bolt, and secured with a washer and nut. A critical part of the assembly is the sill gasket, which is the material which isolates the wood from the potential dampness of the concrete, avoiding mildew, rot and all sorts of bad things when wood gets wet.