The Mac runs like a dream.

　　If your Mac (iMac or MacBook) has been running slowly after years of use, it might be time for some maintenance. Actually, you don't necessarily have to go through a lot of trouble or replace the hardware to boost its running speed. The following methods might be of great help:

　　1. Close High-Energy-Consuming Programs

　　One of the simplest ways to speed up your Mac is to close applications or programs that you're not using. Mac may allocate memory and CPU resources to programs that are not frequently used. Closing them can effectively free up space and reduce the workload. You can use the "Activity Monitor" to view all the processes running on your Mac. This program can be opened via "System Preferences" > "Utilities" or by searching with Command + Spacebar. It displays the resource consumption of each program, categorized by CPU, memory, energy usage, disk, and network. On the "CPU" tab, close applications or programs that you're not using, especially those that consume a large amount of CPU resources.

　    2. Clean Up Startup Items

　　Some applications and programs automatically run every time the system starts up, which could be the main culprit for the slow system performance. You can open "System Preferences", click on "Users & Groups", and select the "Login Items" tab to view and remove programs that you don't want to run at system startup.

　　3. Manage iCloud Sync

　　Syncing files and photos across multiple devices using iCloud can sometimes cause your Mac to run slowly. It's advisable to avoid storing large files and documents on your Mac and only keep necessary documents and files to improve system speed and reduce sync time. If your Mac is busy syncing photos, you can turn off the "iCloud Photos" feature on your device.

　　4. Free Up Storage Space

　　When your Mac's storage space is almost exhausted, its running speed will significantly slow down. Photos, videos, and music files are the main factors that occupy storage space. Purchasing iCloud service doesn't directly solve the storage space problem because files deleted after being backed up to iCloud will be removed from all devices. If you've synced iCloud across all your devices, a large number of files and documents may be stored on your Mac, depleting the storage space. Therefore, it's best to turn off the "iCloud Photos" sync feature on your Mac, use services like DropBox or Google Drive to back up files to the cloud, and then delete them from your computer. For downloaded music files, you can transfer them to an external hard drive or pay for a streaming service (such as Apple Music) to move the music to the cloud, delete it from your Mac, and access it from any device.

　　5. Delete Old Files and Empty the Trash

　　Deleting old files and unused files, as well as emptying the trash, can quickly free up storage space and improve your Mac's running speed. Remember to check your Mac and find and delete old files, documents, and unused files. Also, don't forget to delete items in the "Downloads" folder, which is often overlooked and may contain a large number of forgotten documents and files. Back up old files and documents to an external hard drive and remove them from your Mac. After deletion, remember to empty the trash; otherwise, the deleted files and documents will still occupy storage space. You can also set up system preferences to empty the trash regularly (click on the Apple logo in the menu bar, select "About This Mac", click on "Storage", and then click on "Manage" to set the trash to be automatically deleted every 30 days).

　　6. Reduce or Turn Off Graphic Effects

　　Reducing or turning off graphic effects can help improve your Mac's running speed. Some people prefer to turn off the Dock to avoid performance degradation. You can click on "System Preferences" and then "Dock" in sequence, and uncheck options such as "Magnification", "Animate opening applications", and "Automatically hide and show the Dock". Additionally, you can click on "Minimize windows using" and change the "Genie effect" to the "Scale effect".

　　7. The Last Resort

　　If none of the above methods work, you can try resetting your entire Mac and performing a clean reinstallation of the operating system. This should be considered as a last resort because it requires completely deleting the entire startup disk and clearing all the files in the system library and user library that have been built up over the years. Before doing so, it's recommended to back up all necessary files, documents, photos, music, etc. If your Mac still doesn't show any improvement, it might be time to consider replacing or upgrading it.