for some reason the Google Chrome I installed from the Ubuntu Software Centre is not working. Version number: 9.0.597.94-r73967 (google-chrome-stable). What can be wrong?
Also, what exactly is Chromium web browser? What's the difference between the two. Firefox is working fine, but I prefer Google Chrome.
What do you mean with "non working"? What's the issue you experience? Chromium and Google Chrome is almost the same by the way. Chromium is an open source software, and usually not as stable as Google Chrome. Google releases Chrome based on Chromium regularly. Chrome itself is not entirely an open source software, it contains some not-free pieces as well. Chromium is mainly for developers, but for sure, someone can install it to use ... There are different channels for Chromium, such as snapshots and more stable but less regular versions, it's up to you what you use.
