Paywall
A paywall is a method of restricting access to content via a paid subscription. Beginning in the mid-2010s, newspapers started implementing paywalls on their websites as a way to increase revenue after years of decline in paid print readership and advertising revenue. In academics, research papers are often subject to a paywall and are available via academic libraries that subscribe.
Firewall (construction)
The term firewall is also commonly used in American English to refer to the barrier between the passenger and engine compartments of a vehicle. The inner and outer surfaces of the firewall are often coated with noise, vibration, and harshness (NVH) absorber to prevent most engine noise from reaching the passenger compartment. In British English, the term for this barrier is bulkhead.