64-bit operating systems are popular like never before. Even though 64-bit software is available for some time, web browsers still try to adopt to the more powerful x64 computer architecture. A 64-bit web browser is a software that is capable to use a 64-bit architecture, supported by your processor and operating system. Which means it can process more memory out of your system if necessary.
If you have more than 4 GB of RAM installed on your computer, than you should consider switching to the x64 version of your operating system. A 32-bit operating system is capable of using up to 3.7 GB of RAM even if more memory is installed in your PC.
Among other advantages of the 64-bit platform, the ability to work with more RAM is probably the most important one. This will make native 64-bit software more responsive and faster than the “regular” 32-bit software version.