VirtualBox is a full x86 hardware virtualizer, suitable for server, desktop and embedded usage. It's extremely feature-rich, emulates lots of individual and alternative hardware and devices, supports different virtual machine disk formats, it's cross-platform and supports ancient and current Windows versions, DOS systems, BSD, Solaris and OS/2 as guest operating system.
minor feature: VMM: added support for FSGSBASE, PCID, INVPCID CPU features for guests VMM: EMM386 with detecting suitable page frame base. Front end: Linux: prevent VM window from jumping and auto-resizing to tiny size after resizing it on HiDPI screen. Front end: Linux: seamless regression caused by wm_class functionality. Front end: switched to https downloads. Front end: crash while opening New machine wizard (s.a. forums topic 86592). Audio: added support for distinguishing recording sources in the PulseAudio mixer on the host when multiple VMs are running. Audio: various for the DirectSound backend. Video recording: added better file seeking support and playback of recorded files with certain players (e.g. Firefox). Audio: various for Windows guest surround setups. Audio: various for HDA emulation. Serial: an where the serial port parameters in the emulation and host serial port got out of sync. Storage: overwriting certain INQUIRY data for the DVD/CD drive attached to a AHCI controller. Storage: handling VMDK images created by Amazon EC2 VM export. Network: PXE boot regression in e1000. Network: Added a workaround for older guests which do not enable bus mastering for the virtio PCI device. 3D: add environment variable to configure presenting 3D content on main thread. Windows hosts: indiscriminate binding of NDIS5 bridged driver, that caused PPPOE malfunction. Windows guests: incorrect function error when using shared folders in certain applications. Linux guests: Linux 4.15 support. Linux guests: black screen when 3D enabled in guests. Linux guests: suppress setuid and setgid in shared folders.