A wider bar is indicative of a larger space consumed. You will find just six general classes of information stored on your own Startup Disk. You can view your storage use by choosing This Mac from the Apple menu and switching to the storage area. As soon as you realize what is using up your disc space, you can review your folders and find out the files to select for removal. But it often happens that the most important consumers of disk space will be the 'Other' files, including cookies, caches, archives, logs, disc images, extensions, plugins, and the likes. Photographs, movies or Backups are known to use up the most space. If you would like to check out what is taking up space on the Mac (before finding a solution), feel free to check the current space usage on the device. It comes as a surprise sometimes that you are really out of free space. Therefore, when 'Your disk is almost full' message pops up, you should check your current disk space and start to free up disk space on Mac. When disk is almost full, there are many observable markers like Mac will begin to operate really slow, Mac may crash in some instances, apps become slow to respond, and the system may become overheated.

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