A battery’s lifespan is related to its chemical age, which is more than just the length of time since the battery was assembled. A battery's chemical age results from a complex combination of factors, including temperature history and charging pattern. All rechargeable batteries are consumable components that become less effective as they chemically age. As lithium-ion batteries chemically age, the amount of charge they can hold diminishes, resulting in reduced battery life and reduced peak performance.

Optimized Battery Charging is designed to reduce the wear on your battery and improve its lifespan by reducing the time that your Mac spends fully charged. It uses on-device machine learning to learn your daily charging routine so that it can delay charging past 80% in certain situations, such as when it predicts that your Mac will be connected to power for an extended period of time. Optimized Battery Charging aims to ensure that your Mac is fully charged by the time it expects you to need a full charge. To limit what your Mac considers a full charge, on macOS Tahoe 26.4 or later, you can also set a Charge Limit (see below).

When charging past 80% is delayed by this feature, "Charging On Hold" appears in the battery status menu. If you need your Mac to be charged to 100% sooner, choose "Charge to Full Now" from the menu.

To turn this feature off or on, use the Optimized Battery Charging setting in Battery settings. For example, in macOS Ventura 13 or later:

• From the Apple menu , choose System Settings
• Click Battery in the sidebar
• Click the info button next to Charging (or Battery Health)
• Turn Optimized Battery Charging off or on (when you turn it off, you can choose whether to turn it off only until tomorrow)
• Click Done

Whether using Optimized Battery Charging or Charge Limit, your Mac will occasionally charge to 100% to maintain accurate battery state-of-charge estimates.

Use Charge Limit to set a limit on what your Mac considers a full charge. Your Mac will charge to within a few percentage points of the charge limit, then stop charging and show "Charged to [%] Limit" in the battery status menu. If the battery charge level drops more than 5% while connected to power, charging resumes, again charging to within a few percentage points of the limit.

If your Mac is charged to the limit but you need it to be charged to 100%, choose "Charge to Full Now" from the battery status menu.

To set a charge limit:

• From the Apple menu , choose System Settings
• Click Battery in the sidebar
• Click the info button next to Charging
• Choose a Charge Limit setting between 80% and 100%
• Click Done

macOS's firewall feature blocks unwanted network traffic coming into your computer, and stealth mode makes your Mac essentially invisible to hackers snooping for computers to target. They aren't foolproof features, but they will keep most people from finding and attacking your Mac on public networks.

First, you need to make sure your Mac's firewall is enabled:

• Open "System Settings..." from the  Apple menu
• Go to "Network"
• Click "Firewall" and enable it

Next, enable stealth mode:

• Click "Options..."
• Scroll down and enable "Enable stealth mode" setting
• Click OK

"Automatically allow built-in software to receive incoming connections" and "Automatically allow downloaded signed software to receive incoming connections" should already be checked. Those settings let the apps you already have communicate through the firewall without you having to take any extra steps. Leave those checked unless you know what you're doing and plan to manage app network access manually. You should leave "Block all incoming connections" disabled, unless all you're doing is surfing the Web.

This is a powerful and useful feature that is often overlooked. Here’s how it works:

• From Finder, locate the image you want to convert

• Right-click, control-click, or two-finger click on the image you wish to convert, and go to “Quick Actions” and then select "Convert Image" from the menu

• Select the file format type you wish to convert the image to and select the image size (choose "Actual Size" if you do not want to resize the image), choose whether or not you wish to preserve metadata, then click on the "Convert" button

The image will convert almost instantly and appear in the same folder with the same file name as the origin image. This Quick Action image conversion tool is super fast and powerful, but is limited to JPG, PNG, and HEIF/HEIC formats. If you wish to convert to additional image file formats, you will have to use Preview.

Apple has increasingly made it hard to mess with macOS system files. That’s true whether you intentionally want to extend macOS’s functionality or if a malicious party is trying to install and activate a virus. However, many system components and all Apple and third-party apps rely on preferences and other files to store your custom settings, caches for work in progress, and other data. If those files corrupt, macOS may be perfectly fine, but you can’t get anything done in an app or your account.

Once you’ve gone through troubleshooting your Mac within your account that doesn’t seem to improve matters, the next big leap before reinstalling macOS is to set up a fresh macOS user account. From this account, you can test hardware, like your Wi-Fi or ethernet adapter; add printers and scanners; or run third-party software that keeps crashing on launch.

Because a fresh account typically contains nothing that would already be corrupted, you can isolate whether a problem is in your everyday user account or a system-wide issue–maybe even hardware related.

Here’s how to set up a fresh, new user account:

• Open "System Settings..." from the  Apple menu

• Go to "Users & Groups"

• Click the "Add User..." button

• Enter your password if prompted

• Choose whether to create a Standard or Administrator account, give it a name, password, and hint, and click "Create User"

When making the account, what kind should it be?

Create a Standard account if you want to test a problem from the perspective of a user without any extra privileges.

Create an Administrator if that’s your normal account type–that’s typical–and you’re trying to perform an apples-to-apples comparison.

• Choose  Apple menu > Log Out [name]

• At the login screen, select the new account, enter the password, and click the arrow to log in

Now you can check if your problem persists.

When you’ve debugged your problem, you can get rid of the account. You must be logged in using an Administrator account to do this.

A version is saved automatically every hour, or more frequently when you’re making many changes, when you open, save, duplicate, lock, rename, or revert a document. You can also explicitly save a version.

To browse, restore, duplicate, and delete versions:

1. Open the document, then choose File > Revert To > Browse All Versions.

2. Click tick marks along the timeline to browse versions.

3. Display the version you want, then do one of the following:

• Restore your document to this version: Click Restore
• Duplicate this version in a new document: Press and hold the Option key, then click Restore a Copy
• Delete this version: Move the pointer to the top of the screen to show the menu bar, then choose File > Revert To > Delete This Version
• Leave your document as is: Click Done

To revert a document to the last opened version:

Open the document, choose File > Revert To, then choose Last Opened, Last Saved, or Previous Save

To explicitly save a version:

Open the document, then choose File > Save. To save the document using a different filename, location, or format, press and hold the Option key, then choose File > Save As