This is just the data we know of. You can disable the telemetry settings in Firefox, and it is very likely that hardcore privacy advocates would disable this data collection, so perhaps the amount of encrypted web traffic is slightly higher.
RSA is an encryption method named after the initials of the inventors’ sir names: Ron Rivest, Adi Shamir, and Leonard Adleman. It uses the mathematical “factoring problem” to secure communication. The details of this specific type of encryption will be discussed in an article soon to come.