1. macOS：
macOS是Apple Incorporation提供的一系列专有图形操作系统。它以前被称为Mac OS X，后来被称为OSX。它是专门为Apple mac计算机设计的。它基于Unix操作系统。它是使用C，C++，Objective-C，汇编语言和Swift开发的。它是仅次于Windows的个人计算机中第二使用最多的操作系统。苹果于2001年发布了macOS的第一个版本。
2. OpenBSD：
OpenBSD是由The OpenBSD Project提供的，专注于安全性，免费和开源的操作系统。它基于Berkeley软件发行版。它是一个类似Unix的操作系统。它可用于许多平台，包括服务器，NAS，工作站和嵌入式系统。它基本上是使用C语言，汇编语言，Perl和Unix Shell编写的。 OpenBSD的第一个版本于1995年发布。此操作系统中使用的内核是单片的。
macOS和OpenBSD之间的区别：
| S.No. | MACOS | OPENBSD |
|---|---|---|
| 1. | It was developed and is owned by Apple Incorporation. | It was developed and is owned by The OpenBSD Project. |
| 2. | It was launched in 2001. | It was launched in 1995. |
| 3. | Its target system types are workstation, personal computers and embedded systems. | Its target system types are server, NAS, workstation and embedded systems. |
| 4. | Computer architectures supported by macOS are x86-64(10.4.7-present), IA-32(10.4.4-10.6.8) and PowerPC(10.0-10.5.8). | Computer architectures supported by OpenBSD are IA-32, x86-64, SPARC, 68k, Alpha and VAX. |
| 5. | Its kernel type is Hybrid with modules. | Its kernel type is Monolithic with modules. |
| 6. | Its package management is macOS installer. | Its package management is Ports collection/packages. |
| 7. | Its update management is Software Update. | Its update management is by source or by binary. |
| 8. | Its native APIs are Carbon, Cocoa, Java and BSD-POSIX. | Its native APIs are BSD-POSIX. |
| 9. | It has the preferred license of Proprietary, APSL and GNU GPL. | It has the preferred license of ISC. |
| 10. | The non-native APIs supported by its subsystems are Toolbox, Win16 and Win32. | The non-native APIs are not supported through its subsystems. |
| 11. | File systems supported by macOS are HFS+, APFS, HFS, UFS, AFP, ISO 9660, FAT, UDF, NFS, SMBFS, NTFS, FTP, WebDAV and ZFS. | File systems supported by OpenBSD are ffs, ext2, FAT, ISO 9660 and NFS. |