Well after a lot of computer usage, installing, uninstalling, downloading and general use the computer will create links to all the files and collect data in a big database called registry.
In the registry there is information on everything that happens on the computer and after a long time or a lot of activity the computer will get bogged down within this database, as it gets bigger and bigger the computer will get slow and slower because it takes so long to search the registry for the information you are seeking. So cleaning out the registry will slightly increases the speed of your computer by deleting old, unused or incorrect records that are held inside the registry. Thus making searches quicker for the information your computer is looking for in the registry.
How to clean the Registry
There are many ways to clean the registry but not all of them are safe or easy, but there is one key rule when doing any work on the registry is to make a backup first, because if you delete something by mistake you could corrupt your Windows install and without a backup you would have to reinstall windows or use a repair tool.
To clean your registry the easy way you are going to need to download some software that is free and can check your entire registry automatically and tell you if there are any errors and what needs to be done about it. The software will also apply the fixes for you, so you don't have to worry about that. So to download the software, go to Google and search for cleaner, this software can also clean up internet history and other unused files.
Once the search has completed you see a link for Piriform this is the correct site for the download, click on it and then click on the green download button on the website. Then scroll down to the download link that is from Filehippo, now in the top right side of the screen will be a green download button click on that, now your download will start automatically. If the option pops up to run, save, or cancel click on run.
Once the installation starts you'll be shown a screen to select your language, select language and click ok. Then click next, and then click I agree, then click next again, and now you should see the option to install Google toolbar, this is optional and can be unmarked, now click on the install button. Once the install has completed it will ask you one last question if you want to run Ccleaner, leave marked and click the finished button.
When Ccleaner first opens you'll be asked a question about intelligent cookie scan, this is to save all your passwords for thing s like Hotmail, Facebook etc, you don't have to yes but it is recommend you do, to save you time when logging into such sites. Now after clicking yes or no you'll be brought to a screen that gives you two options, to analyze or to run cleaner, you can run the analyzer first if you want to see the files it's going to fix. This isn't the registry but can also help speed up your computer.
This scan might take some time to complete. If you click on run cleaner you'll get a message box pop up warning that the files will be permanently delete from your computer click ok to continue, again this can take a long time. Now to clean your registry you'll need to click on registry button (the cube icon on the left) and then click on scan for issues button. This will check for any issues and will report them to you.
When the scan has been completed click on fix selected issues. The software will then ask you if you want to make a back up select yes and place the backup file somewhere you'll be able to find it again should anything go wrong. Now you'll have the option to fix issues one by one or fix all selected issues click on fix all selected issues unless you need to check each one. Once complete click on close and now you've just cleaned your computer of old files and cleaned up the registry to increase your computer speeds.