VMware, Inc. is a subsidiary of Dell Technologies that provides cloud computing and platform virtualization software and services. It was the first commercially successful company to virtualize the x86 architecture.

VMware's desktop software runs on Microsoft Windows, Linux, and macOS, while its enterprise software hypervisor for servers, VMware ESXi, is a bare-metal hypervisor that runs directly on server hardware without requiring an additional underlying operating system.

In 1998, VMware was founded by Diane Greene, Mendel Rosenblum, Scott Devine, Ellen Wang and Edouard Bugnion. Greene and Rosenblum, who are married, first met while at the University of California, Berkeley. Edouard Bugnion remained the chief architect and CTO of VMware until 2005, and went on to found Nuova Systems (now part of Cisco). For the first year, VMware operated in stealth mode, with roughly 20 employees by the end of 1998. The company was launched officially early in the second year, in February 1999, at the DEMO Conference organized by Chris Shipley. The first product, VMware Workstation, was delivered in May 1999, and the company entered the server market in 2001 with VMware GSX Server (hosted) and VMware ESX Server (hostless).

In 2003, VMware launched VMware Virtual Center, the VMotion, and Virtual SMP technology. 64-bit support was introduced in 2004.

On January 9, 2004, EMC (now Dell EMC) acquired the company.

On August 14, 2007, EMC sold 15% of VMware to the public via an initial public offering. Shares were priced at US$29 per share and closed the day at US$51.

On July 8, 2008, after disappointing financial performance, the board of directors fired VMware co-founder, president and CEO Diane Greene, who was replaced by Paul Maritz, a retired 14-year Microsoft veteran who was heading EMC's cloud computing business unit.

On September 10, 2008, Mendel Rosenblum, the company's co-founder, chief scientist, and the husband of Diane Greene, resigned.

On September 16, 2008, VMware announced a collaboration with Cisco Systems. One result was the Cisco Nexus 1000V, a distributed virtual software switch, an integrated option in the VMware infrastructure.

In April 2011, EMC transferred control of the Mozy backup service to VMware.

On April 12, 2011, VMware released an open source platform-as-a-service system called Cloud Foundry, as well as a hosted version of the service. This supported application deployment for Java, Ruby on Rails, Sinatra, Node.js, and Scala, as well as database support for MySQL, MongoDB, Redis, Postgres, RabbitMQ.

In March 2013, VMware announced the corporate spin-off of Pivotal Software, with General Electric making an investment in the company. All of VMware's application- and developer-oriented products, including Spring, tc Server, Cloud Foundry, RabbitMQ, GemFire, and SQLFire were transferred to this organization.

In May 2013, VMware launched its own IaaS service, vCloud Hybrid Service, at its new Palo Alto headquarters (vCloud Hybrid Service now known as vCloud Air), announcing an early access program in a Las Vegas data center. The service is designed to function as an extension of its customer's existing vSphere installations, with full compatibility with existing virtual machines virtualized with VMware software and tightly integrated networking. The service is based on vCloud Director 5.1/vSphere 5.1.

In September 2013, at VMworld San Francisco, VMware announced general availability of vCloud Hybrid Service and expansion to Sterling, Virginia, Santa Clara, California, Dallas, Texas, and a service beta in the UK. It announced the acquisition Desktone in October 2013.

In January 2016, in anticipation of Dell's acquisition of EMC, VMware announced a restructuring to reduce about 800 positions, and some executives resigned. The entire development team behind VMware Workstation and Fusion was disbanded and all US developers were immediately fired. On April 24, 2016, maintenance release 12.1.1 was released. On September 8, 2016, VMware announced the release of Workstation 12.5 and Fusion 8.5 as a free upgrade supporting Windows 10 and Windows Server 2016.

In April 2016, VMware president and COO Carl Eschenbach left VMware to join Sequoia Capital, and Martin Casado, VMware's general manager for its Networking and Security business, left to join Andreessen Horowitz. Analysts commented that the cultures at Dell and EMC, and at EMC and VMware, are different, and said that they had heard that impending corporate cultural collisions and potentially radical product overlap pruning, would cause many EMC and VMware personnel to leave; VMware CEO Pat Gelsinger, following rumours, categorically denied that he would leave.

Mozy was transferred to Dell in 2016 after the merger of Dell and EMC.

In April 2017, according to Glassdoor, VMware was ranked 3rd on the list of highest paying companies in the United States.

In Q2 2017, VMware sold vCloud Air to French cloud service provider OVH

In March 2015, the Software Freedom Conservancy announced it was funding litigation by Christoph Hellwig against VMware for violation of his copyrights in its ESXi product. The case will be heard in Hamburg, Germany. The SFC claims VMware is using both the Linux kernel and Busybox without respecting the terms of the GPL copyright license, while VMware told journalists that it believed the case was without merit and expressed disappointment that Conservancy had resorted to litigation.

VMware's most notable products are its hypervisors. VMware became well known for its first type 2 hypervisor known as GSX. This product has since evolved into two hypervisor products lines: VMware's type 1 hypervisors running directly on hardware and their hosted type 2 hypervisors.

VMware software provides a completely virtualized set of hardware to the guest operating system. VMware software virtualizes the hardware for a video adapter, a network adapter, and hard disk adapters. The host provides pass-through drivers for guest USB, serial, and parallel devices. In this way, VMware virtual machines become highly portable between computers, because every host looks nearly identical to the guest. In practice, a system administrator can pause operations on a virtual machine guest, move or copy that guest to another physical computer, and there resume execution exactly at the point of suspension. Alternatively, for enterprise servers, a feature called vMotion allows the migration of operational guest virtual machines between similar but separate hardware hosts sharing the same storage (or, with vMotion Storage, separate storage can be used, too). Each of these transitions is completely transparent to any users on the virtual machine at the time it is being migrated.

VMware Workstation, Server, and ESX take a more optimized path to running target operating systems on the host than that of emulators (such as Bochs) which simulate the function of each CPU instruction on the target machine one-by-one, or that of dynamic recompilation which compiles blocks of machine-instructions the first time they execute, and then uses the translated code directly when the code runs subsequently (Microsoft Virtual PC for macOS takes this approach). VMware software does not emulate an instruction set for different hardware not physically present. This significantly boosts performance, but can cause problems when moving virtual machine guests between hardware hosts using different instruction sets (such as found in 64-bit Intel and AMD CPUs), or between hardware hosts with a differing number of CPUs. Software that is CPU agnostic can usually survive such a transition, unless it is agnostic by forking at startup, in which case, the software or the guest OS must be stopped before moving it, then restarted after the move.

VMware's products predate the virtualization extensions to the x86 instruction set, and do not require virtualization-enabled processors. On newer processors, the hypervisor is now designed to take advantage of the extensions. However, unlike many other hypervisors, VMware still supports older processors. In such cases, it uses the CPU to run code directly whenever possible (as, for example, when running user-mode and virtual 8086 mode code on x86). When direct execution cannot operate, such as with kernel-level and real-mode code, VMware products use binary translation (BT) to re-write the code dynamically. The translated code gets stored in spare memory, typically at the end of the address space, which segmentation mechanisms can protect and make invisible. For these reasons, VMware operates dramatically faster than emulators, running at more than 80% of the speed that the virtual guest operating system would run directly on the same hardware. In one study VMware claims a slowdown over native ranging from 0–6 percent for the VMware ESX Server.

VMware's approach avoids some of the difficulties of virtualization on x86-based platforms. Virtual machines may deal with offending instructions by replacing them, or by simply running kernel code in user mode. Replacing instructions runs the risk that the code may fail to find the expected content if it reads itself; one cannot protect code against reading while allowing normal execution, and replacing in place becomes complicated. Running the code unmodified in user mode will also fail, as most instructions which just read the machine state do not cause an exception and will betray the real state of the program, and certain instructions silently change behavior in user mode. One must always rewrite, performing a simulation of the current program counter in the original location when necessary and (notably) remapping hardware code breakpoints.

Although VMware virtual machines run in user mode, VMware Workstation itself requires the installation of various device drivers in the host operating system, notably to dynamically switch the Global Descriptor Table (GDT) and the Interrupt Descriptor Table (IDT).

The VMware product line can also run different operating systems on a dual-boot system simultaneously by booting one partition natively while using the other as a guest within VMware Workstation.

VMware ESXi, an enterprise software product, can deliver greater performance than the freeware VMware Server, due to lower system computational overhead. VMware ESXi, as a "bare-metal" product, runs directly on the server hardware, allowing virtual servers to also use hardware more or less directly. In addition, VMware ESXi integrates into VMware vCenter, which offers extra services

The VMware Workspace Portal was a self-service app store for workspace management.

VMware's storage and availability products are composed of two primary offerings:

VMware NSX is VMware's network virtualization product marketed using the term software-defined data center (SDDC). The technology included some acquired from the 2012 purchase of Nicira.

Workspace ONE allows mobile users to access to apps and data.

The VIX (Virtual Infrastructure eXtension) API allows automated or scripted management of a computer virtualized using either VMware's vSphere, Workstation, Player, or Fusion products. VIX provides bindings for the programming languages C, Perl, Visual Basic, VBscript and C#.