After starting your personal computer the application you intuitively reach for with your mouse pointer is the web browser. Most web browsers greet you with a input field of all input fields - the search box. Once you do a search you eventually arrive at a website.
While evaluating and working on your own website and content management system. You have most likely arbitrarily pieced together the architecture of your website. Resulting of Your website being served by the ubiquitous application shell - web browser. Web browser residing on your website's end user's device sending a request to your website's domain name. The domain name pointing to a server hosting your website.
The web browser, making a request to web server, for the document being requested, and the data transaction passing through the various separation of concerns. Server side script engine, web server, http packets, transmission control protocol, wide area network, local area network, and arriving at a users web browser.
There are separation of concerns within the web browser it self. Most recently introduced separation is sand-boxing of displayed content in browser tabs.
"Nov 9, 2016 - Google is tackling high memory consumption by its Chrome browser, ... problems as Google highlighted in a study of 760,000 sites caught by Safe Browsing." (https://www.zdnet.com/article/google-to-malware-sites-well-brand-you-deceptive-for-a-month-no-reviews-allowed/)"760,000 sites.."
"Feb 22, 2016 - The website has been down for most of Sunday, potentially losing thousands of downloads. ... Chrome: 70% of all security bugs are memory safety issues." (https://www.zdnet.com/article/hacker-hundreds-were-tricked-into-installing-linux-mint-backdoor/)"..memory safety issues."
"Mar 11, 2020 - Academics break TRR protections on RAM cards for new Rowhammer attacks. ... The list below summarizes the most important papers and advances in Rowhammer attacks: Academics showed how a.." (https://www.zdnet.com/article/modern-ram-used-for-laptops-smartphones-still-vulnerable-to-rowhammer-attacks/)"Academics break TRR protection.."
"May 23, 2020 - Chrome: 70% of all security bugs are memory safety issues ... These memory management vulnerabilities are the most sought-after bugs that ... and have recently rolled out Site Isolation, a feature that puts each site's resources into its ... cyber attacks.." (https://www.zdnet.com/google-amp/article/chrome-70-of-all-security-bugs-are-memory-safety-issues/)"..70% of all security bugs.."