VirtualBox是一款免費且開源的虛擬化軟體，允許用戶在電腦上創建和運行虛擬機器。使用VirtualBox，用戶可以在不需要創建單獨的分區或購買額外硬體的情況下，在電腦上同時安裝和運行多個操作系統。

VirtualBox 的主要優勢之一是其易於使用。即使是對虛擬化技術幾乎沒有經驗的人，也可以輕鬆安裝和設置。VirtualBox 還提供廣泛的自定義選項，包括調整分配給每個虛擬機的 RAM、CPU 核心和硬碟空間的能力。

VirtualBox的另一個優點是其與多種作業系統的兼容性。使用者可以在其虛擬機器上安裝和運行Windows、Linux、macOS以及其他許多作業系統。這使得它成為開發人員、軟體測試人員以及需要在單一電腦上運行多個作業系統的人的絕佳工具。

VirtualBox 也提供了一系列的進階功能，如對 USB 設備、共享資料夾和網路配接器的支持。這些功能使得運行需要硬體或網路資源的軟體成為可能，如虛擬路由器、防火牆和伺服器。

VirtualBox 是需要在單一電腦上運行多個作業系統的人的極佳選擇。其易用性、多樣化的自訂選項以及與許多不同作業系統的相容性，使其成為開發人員、IT 專業人士和家庭用戶皆適用的多功能且強大的工具。

關鍵特性：

• 跨平台相容性。
• 直觀的圖形用戶介面。
• 支援各種作業系統。
• 與主機作業系統無縫整合。
• 快照和克隆。
• 網路功能。
• 虛擬設備支援。
• 擴充套件以增加功能。

• VMM: fix for a bug in the Local APIC emulation causing a BSOD when booting certain guests (4.3.0 regression; bug #12240)
• VMM: fixed loading of saved states if VT-x/AMD-V was disabled (4.3.2 regression; bug #12291)
• VMM: fixed single-stepping inside the guest for certain instructions (VT-x only; bug #10947)
• VMM: fixed a performance issue involving APIC accesses after rebooting a VM (4.3.0 regression; VT-x only; bug #12296)
• VMM: fixed TPR patching to be enabled for 32-bit guests even when the chosen guest type is 64-bit (4.3.0 regression; AMD-V only)
• VMM: fixed occasional VINF_EM_TRIPLE_FAULT errors on hosts without the unrestricted guest execution feature (bug #12198)
• GUI: don't bother the user with the BPP warning if no Guest Additions are installed
• GUI: fixed machine-window paint artifacts on VM reboot / guest-screen resize
• GUI: make sure the assigned license and description are attached to the exported appliance
• GUI: fixed bugs in close VM action restrictions handling (bug #12333)
• GUI: fixed incorrect wizards text colors for some unusual look and feel styles (bug #11743)
• GUI: should restore seamless mode as soon as possible after VM reboot or shutdown
• GUI: fixes for medium enumeration
• GUI: the OS X hot corners were not accessible while a VirtualBox VM is running (Mac OS X hosts only; bug #4139)
• GUI: fixed an old bug which bared the host from cleanly shutdown / reboot if the VM selector window is open (Mac OS X hosts only; bug #8254)
• Host-only Networking: fixed creating of host-only network interfaces (4.3.0 regression; bug #12182)
• NAT: don't run into an infinite loop in case the host cannot access any DNS server (4.3.0 regression; bug #12300)
• NAT: don't re-connect the cable if the DNS information changes and the cable was disconnected before (4.3.0 regression; bug #12225)
• NAT: fixed several issues with automatically starting / terminating of NAT networks on VM start / stop and configuration changes
• VBoxNetDHCP: don't block prevent VBoxSVC from terminating (bug #12264)
• 2D Video acceleration: fix crashes on presentation mode switches (bug #9194)
• BusLogic: allow to run VMs with more than one BusLogic SCSI controller enabled
• Keyboard: fixed a VM crash if a VM was resumed from a saved state where at least one key was pressed (bug #11289)
• VBoxSVC: fixed a heap corruption under certain conditions (4.3.0 regression)
• VBoxSVC: fixed a race leading to a hang during initialization (bug #12349)
• OVF: fixed import logic for OVF appliances containing multiple VMs
• OVF: improved logic for finding an appropriate image format during OVF import
• API: block the removal of the current snapshot if it has child snapshots (only relevant for VMs without snapshottable hard disks, their presence always prevented removal), which resulted in VM configuration corruption
• API: mark VM configurations with snapshots but without current snapshot as inaccessible, as this combination is nonsense
• API: fixed information for some automatically generated events (only with XPCOM, Windows host was not affected), which caused errors when getting some of the attributes over the webservice (bug #12379)
• SDK: extended the functionality coverage for the C bindings
• Guest Control: various bug fixes and improved VBoxManage help (bugs #8072, #11044, #12336, #12338, #12346, #12371)
• Windows hosts: another attempt to fix the massive DPC latency (bug #6242)
• Windows host installer: make registering file extensions optional, contributed by Tal Aloni (bug #8009)
• Mac OS X hosts: properly sign the kernel extensions for Mavericks hosts (bug #12256)
• Mac OS X hosts: fixed a bug where the VirtualBox dock icon was not properly removed from the dock after a VM terminated preventing Mavericks hosts from shutting down (bug #12241)
• Mac OS X hosts: fixed minor installer issue (bug #12275)
• Linux hosts / guests: Linux 3.13 compile fixes (bug #12358)
• Linux guests: build the vboxvideo kernel module correctly on OL/RHEL 6.1 guests (bug #11996)
• Linux guests: make 3D work on Slackware 14.1 (bug #12320 comments 3 and 4)
• Guest Additions/3D: fixed an occasional dead-lock (bug #12319)
• Windows Additions/3D: fixed possible memory leaking (bug #12228)
• Windows Additions/XPDM: use separate tables containing valid video modes for each virtual monitor
• Windows Additions: fixed automatic logins for Vista and newer Windows guests (bug #12332)