The “Anti-Circumvention” provision (sections 1201 et seq. of the Copyright Act) was put in place to discourage copyright pirates from circumventing and trafficking in copyrighted content. (i.e. peer to peer file exchanges, limiting how many times you can copy software onto different computers)
The “Safe Harbor” provision (sections 512 et seq. of the Copyright Act) limits the liability of Internet Service Providers (ISP) for the alleged copyright infringement of its users. Without this provision, the risk of potential copyright liability would prevent ISP’s from providing their services or transmitting content.