Old files that you no longer use or need will take up space that can really slow your computer down and clog up the memory in your hard drive.  First locate your Downloads and Documents folders. This is where a lot of your computer’s memory is dedicated. Locate files in each folder that you no longer need and move them into your trash. An easy way to go about this is to click the “Date modified” column and sort your files based on the last date a file was opened starting from earliest to most recent. Delete the files you haven’t used in a long time, or transfer them to an external hard drive if you need to save them. Like with your downloads and documents, we tend to install a fair amount of applications that we don’t end up using very often, if ever. These applications don’t just take up memory from being installed, but they also take up data that can affect your computer’s speed and memory.  If you are on a Mac, you can find your Applications folder from your Finder. Click Go > Applications. Then, just like you did with your documents and downloads, sort them by Date Modified and locate the ones you haven’t used in a while first. Delete all the applications you can live without.  If you are on a PC, click your Start button > Control Panel > Programs > Programs and Features. Select a program you don’t need and click “Uninstall”. On a Mac, just emptying your trash doesn’t completely delete all the information of your files, it just removes them from your file directory. To completely delete your files from your computer, click Finder > Secure Empty Trash.  On Windows in order to truly delete files you have to use a third party program to rid your hard drive of any leftover files after you’ve emptied your recycle bin. Popular programs are Eraser, CCleaner, or SDelete, which is a tool from Microsoft which allows you to empty files through a command line prompt.  Make absolutely sure you have appropriately deleted what you don't need or want (but be sure you don't delete something you do need, or your computer...

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Write a summary of the previous text in Indonesian:
Hapuslah berkas-berkas lama. Hapuslah aplikasi yang tidak dibutuhkan. Hapuslah semua berkas yang ada di keranjang sampah sebab berkas tersebut tetap mengambil memori dari komputer. Matikan lalu nyalakan kembali komputer agar hard drive segera membersihkan dan memperbarui data.