You might find you computer slow down significantly after you use it. Sometimes it happens when you are just browsing the internet. It is pretty common if I check the memory usage and it exceed 1GB used. Chance are your web browser (Firefox, Chrome, Internet Explorer) is leaking memory. Even though it is a too big in these days’ standard, it did slow down computer a lot.
Firefox support forum did provide some options for solving it:
Based on my experience, minimize Tabs and restart Firefox are the two most effective ways to solve the problem.
I often read PDF documents from the browser, it seems to be a big consumer of the memory. By default it will open PDF with a build-in viewer and sometimes it will keep memory consumption even if you closed the viewed tab. So here is another trick you want to use if you are like me.
Always open PDF with external application and not in Firefox itself. Follow the instruction here: https://support.mozilla.org/en-US/kb/disable-built-pdf-viewer-and-use-another-viewer
After doing these, my computer is noticeably faster.
Hope it works for you the same.