There are new operating systems, but Apple has made some slight changes to the base system requirements for each OS:

iOS 18iOS 18 brings no changes in compatibility:

• iPhone 15 line
• iPhone 14 line
• iPhone 13 line
• iPhone 12 line
• iPhone 11 line
• iPhone XS and XS Max
• iPhone XR
• iPhone SE (2nd generation or later)

iPadOS 18iPadOS 18 seems to drop the 6th-generation iPad. RIP, buddy.

• iPad Pro (M4)
• iPad Pro 12.9-inch (3rd generation and later)
• iPad Pro 11-inch (1st generation and later)
• iPad Air (M2)
• iPad Air (3rd generation and later)
• iPad (7th generation and later)
• iPad mini (5th generation and later)

macOS SequoiaSequoia has no compatibility changes when compared to Sonoma:

• iMac Pro (2017)
• Mac mini (2018 and later)
• MacBook Pro (2018 and later)
• MacBook Air (2020 and later)
• iMac (2019 and later)
• Mac Pro (2019 and later)
• Mac Studio (2022 and later)

Apple IntelligenceApple Intelligence is a wide ranging set of features across these three operating systems, with its own set of system requirements:

• iPhone 15 Pro and Pro Max (A17 Pro)
• iPad Pro (M1 and later)
• iPad Air (M1 and later)
• MacBook Air (M1 and later)
• MacBook Pro (M1 and later)
• iMac (M1 and later)
• Mac mini (M1 and later)
• Mac Studio (M1 Max and later)
• Mac Pro (M2 Ultra)

Apple says:

Apple Intelligence is free to use and will initially be available in U.S. English. Coming in beta this fall.