Panther's system requirements are:

• PowerPC G3, G4, or G5 processor (at least 233 MHz)
• Built-in USB
• At least 128 MB of RAM (256 MB recommended, minimum of 96 MB supported unofficially)
• At least 1.5 GB of available hard disk space
• CD drive
• Internet access requires a compatible service provider; iDisk requires a .Mac account

Video conferencing requires:

• 333 MHz or faster PowerPC G3, G4, or G5 processor
• Broadband internet access (100 kbit/s or faster)
• Compatible FireWire DV camera or web camera

Because a New World ROM was required for Mac OS X Panther, certain older computers (such as beige Power Mac G3s and 'Wall Street' PowerBook G3s) were unable to run Panther by default. Third-party software (such as XPostFacto) can, however, override checks made during the install process; otherwise, installation or upgrades from Jaguar fails on these older machines.

Panther still fully supported the Classic environment for running older Mac OS 9 applications, but made Classic application windows double-buffered, interfering with some applications written to draw directly to screen.

Apple advertised that Mac OS X Panther had over 150 new features, including:

• Finder: Updated with a brushed-metal interface, a new live search engine, customizable Sidebar, secure deletion, colored labels (resurrected from classic Mac OS) in the filesystem and Zip support built in. The Finder icon was also changed.
• Fast user switching: Allows a user to remain logged in while another user logs in, and quickly switch among several sessions.
• Exposé: Helps the user manage windows by showing them all as thumbnails.
• TextEdit: TextEdit now is also compatible with Microsoft Word (.doc) documents.
• Xcode developer tools: Faster compile times with gcc 3.3.
• Preview: Increased speed of PDF rendering.
• QuickTime: Now supports the Pixlet high-definition video codec.

• Font Book: A font manager which simplifies viewing character maps, and adding new fonts that can be used systemwide. The app also allows the user to organize fonts into collections.
• FileVault: On-the-fly encryption and decryption of a user's home folder.
• iChat AV: The new version of iChat. Now with built-in audio- and video conferencing.
• X11: Compatibility for applications based on the X Window System, commonly used for UNIX applications, is available through an optional install, found in the install disk. Mac OS X Panther is the first macOS version to officially support X11. It utilizes Quartz to provide hardware accelerated graphics and is based on the XFree86 implementation of X Window System.
• Safari: A new web browser that was developed to replace Internet Explorer for Mac when the contract between Apple and Microsoft ended, although Internet Explorer for Mac was still available. Safari 1.0 was included in an update in Jaguar but was used as the default browser in Panther.

• Microsoft Windows interoperability improvements, including out-of-the-box support for Active Directory and SecurID-based VPNs.
• Built-in fax support, with Address Book integration.:  Sending a fax can be done using the native Print dialog. To receive faxes, users must pre-configure in System Preferences on how the system should handle an incoming fax, with options  including selecting a folder to save the incoming faxes, to automatically email to an address or to print via a selected printer, upon receiving of the fax.
• Secure Empty Trash, was a feature added in Mac OS X Panther to ensure files that are deleted cannot be recovered, through the use of data erasure techniques.

Panther was Apple's earliest version of Mac OS X that supported WPA and WPA2 security for wireless networks (with the AirPort 4.2 software update).