What is a contact cleaner and why are CAIG products unique?

What is a contact cleaner, and why do you think DeoxIT® contact cleaner and its companion, DeoxIT® GOLD is better than other products?
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Generic contact cleaners use solvents to flush away surface contamination on metal surfaces. However, oxides and sulfides become an integral part of the contact surface and cannot be removed by ordinary contact cleaners. DeoxIT® contact cleaner and DeoxIT® GOLD are unique in that they not only remove surface contamination, they also improve conductivity and prevent the contaminants from re-attaching themselves to the contact/connector surface. Mere solvents are incapable of accomplishing this task.

NOTE:
DeoxIT® GOLD (formerly ProGold)
DeoxIT® SHIELD (formerly PreservIT)
DeoxIT® FaderLube (formerly CaiLube MCL)
DeoxIT® Grease Type M260 & L260 Paste (formerly CaiLube Grease).