Browsers - Web safe

Once I have finished the website I will be testing it in multiple browsers across and across different platforms, for example I will need to test the big main browsers: Chrome, Safari, Opera, Internet explorer, Firefox on both Pc and Mac where possible. From this I will be able to see the differences in the style of the browser.

A user could have different plugins, versions, types, not using the latest/newest standards, settings, different options turned on/off e.g. images in their browser as well as working on a mac/pc/linux based machine as well as their screen resolution, size and and aspect ratio and also which accessibility features they have turned on/off.
A mixture of these will cause a website to show differently in a particular browser.

I will not be able to get the site looking exactly the same for each individual user, what really matters is the usability of it.
Any users will not notice the difference what they will notice is the usability of the site which is the main concern.

http://mygloss.com/geek/files/2010/07/web-browsers.jpg