backpacking vs roaming

backpacking

noun
  • hiking and camping overnight in backcountry with one's gear carried in a backpack. 

  • low-cost, generally urban, travel with minimal luggage and frugal accommodations. 

roaming

noun
  • An instance of wandering. 

  • Using the OS service of manipulating folders and documents from different PC devices by a registered user. 

  • The use of a network or service from different locations or devices. 

  • The ability to use a cell phone outside of its original registering zone. 

How often have the words backpacking and roaming occurred in a corpus of books? (source: Google Ngram Viewer )