1. FreeBSD：
FreeBSD是FreeBSD项目提供的一个免费的开源操作系统。它是基于两个类似Unix的操作系统Berkeley Software Distribution(BSD)和Research Unix设计的。它与Linux操作系统非常相似。它是较早的著名操作系统之一，但是现在与其他操作系统相比，它的使用率有所降低。 FreeBSD的第一个版本于1993年发布。FreeBSD的最新稳定版本是12.1。
2. Solaris：
Solaris是Oracle Corporation提供的专有操作系统。它是一个类似Unix的操作系统。它是用C语言和C++编写的。它具有混合源模型，即同时打开和关闭源。它最初由Sun Microsystems开发，并于2010年被Oracle Corporation收购。Solaris的第一个版本于1992年发布。此操作系统中使用的内核是Monolithic，具有可动态加载的模块。
Solaris和FreeBSD之间的区别：
| Solaris | FreeBSD |
|---|---|
| It was developed by Sun Microsystems. | It was developed and is owned by The FreeBSD Project. |
| It was launched in 1992. | It was launched in 1993. |
| Its target system types are server and workstation. | Its target system type is server, workstation, NAS and embedded systems. |
| Computer architectures supported by Solaris are IA-32, x86-64 and SPARC. | Computer architectures supported are IA-32, x86-64, ARM, MIPS and PowerPC. |
| Its kernel type is Monolithic with dynamically loadable modules. | Kernel type is Monolithic with modules. |
| Its native APIs are SysV/POSIX, GTK and Java. | The native APIs are BSD/POSIX. |
| It has the preferred license of CDDL. | Preferred license is BSD. |
| Its package management is SysV packages or Image Packaging System. | Its package management is MSI. |
| File systems supported by Solaris are UFS, ZFS, ext2, FAT, ISO 9660, UDF, NFS and QFS. | File systems supported are UFS2, ZFS, ext2, ext3, FAT, ISO 9660, UDF and NFS. |