The Steam client functions include update maintenance, cloud storage, and community features such as direct messaging, an in-game overlay, discussion forums, and a virtual collectable marketplace.

Steamworks, an application programming interface (API) released in 2008, is used by developers to integrate Steam's functions, including digital rights management (DRM), into their products.

During this time users faced problems attempting to play; part of legal issues that Valve had with Vivendi, who claimed that physical copies they published could not be activated as to them the game had not been released.

[20] In 2011, some Electronic Arts games, such as Crysis 2, Dragon Age II, and Alice: Madness Returns, were removed from sale because of terms of service that prevented them having their own in-game storefront for downloadable content.

[21][22][23][24] In 2019, Ubisoft announced that it would stop selling future games on Steam, starting with Tom Clancy's The Division 2 because Valve would not modify its revenue sharing model.

[33] Valve intended to "make DRM obsolete" as games released on Steam had traditional anti-piracy measures, including the assignment and distribution of product keys and support for digital rights management software tools such as SecuROM or non-malicious rootkits.

[45] Within Family View, introduced in January 2014, parents can adjust settings for their children's tied accounts, limiting the functionality and accessibility to the Steam client and purchased games.

[50] Valve later changed its policy to be similar to that of Electronic Arts' Origin platform, in which blocked users can still access their games but are heavily restricted, limited to playing in offline mode and unable to participate in Steam Community features.

[110] Steam Guard was advertised to take advantage of the identity protection provided by Intel's second-generation Core processors and compatible motherboard hardware, which allows users to lock their account to a specific computer.

[120][121] In December 2015, Steam's content delivery network was misconfigured in response to a DDoS attack, causing cached store pages containing personal information to be temporarily exposed for 34,000 users.

[122][123] Valve added new privacy settings to Steam in April 2018, allowing users to hide their activity status, game lists, inventory, and other profile elements.

[126] In August 2019, a security researcher exposed a zero-day vulnerability in the Windows client of Steam, which allowed for any user to run arbitrary code with LocalSystem privileges using just a few simple commands.

The Workshop was originally used for distribution of new in-game items for Team Fortress 2;[200] it was redesigned to extend support for any game in early 2012, including modifications for The Elder Scrolls V: Skyrim.

[214][215][216] SteamVR is a virtual reality hardware and software platform developed by Valve, with a focus on allowing "room-scale" experiences using positional tracking base stations, as opposed to those requiring the player to stay in a singular location.

[231] In January 2013, Newell stated that Valve recognized that its role in Greenlight was perceived as a bottleneck, something the company was planning to eliminate in the future through an open marketplace infrastructure.

[228] Valve opted to set the Direct fee at $100 after reviewing concerns from the community and outlined plans to improve their discovery algorithms and inject more human involvement to help these.

For example, an initial experiment released at launch was the Interactive Recommender, which uses artificial intelligence algorithms pulling data from the user's past gameplay history to suggest new games that may be of interest to them.

[269] Other actions taken by developers against the terms of service or other policies have prompted Valve to remove games,[270] which has included asset flips, [271] review manipulation,[272] misuse of Steamworks tools,[273][274][275] and hostile activities towards Steam users.

[279] Valve updated policies in February to ban games that encorporated paid advertising as part of the gameplay cycle, such as viewing an ad for virtual rewards.

[288] In March 2019, Valve faced pressure over Rape Day, a planned game described as being a dark comedy and power fantasy where the player would control a serial rapist amid a zombie apocalypse.

In addition to the Steam client, several features were made available to developers, allowing them to take advantage of the cross-platform Source engine and Steamworks' platform and network capabilities.

[328] Valve's Counter-Strike: Global Offensive also supports Steamworks and cross-platform features on the PlayStation 3, including using keyboard and mouse controls as an alternative to the gamepad.

Valve's Erik Johnson stated that Microsoft required new content on the console to be certified and validated before distribution, which would limit the usefulness of Steamworks' delivery approach.

[390] Steam Spy was credited with being reasonably accurate, but in April 2018, Valve added new privacy settings that defaulted to hiding user game profiles, stating this was part of compliance with the General Data Protection Regulation (GDPR) of the European Union.

[391] A few months later, another method had been developed using game achievements to estimate sales with similar accuracy, but Valve shortly changed the Steam API that reduced its functionality.

[430] The French gaming trade group, Syndicat National du Jeu Vidéo, noted that geo-blocking was a necessary feature to hinder inappropriate product key reselling.

[431] The Commission found, in January 2021, that Valve and co-defendants had violated antitrust rules of the European Union, issued combined fines of €7.8 million, and determined that these companies may be further liable to lawsuits from affected consumers.

[435] A separate class-action lawsuit filed against Valve by Wolfire Games in April 2021 asserted that Steam is essentially a monopoly, since developers must sell to PC users through it and that its 30% cut and "most favored nation" pricing practices violate antitrust laws as a result of their position.

[438] Wolfire refiled its case, narrowing the complaint to Valve's use of its dominance to intimidate developers that sell their game for less on other marketplaces, which the judge allowed to proceed in May 2022.

[440] Valve changed the Steam terms of service in September 2024 to eliminate the forced arbitration clause, such that any disputes with the storefront are to be resolved within courtrooms, and allowing for class-action lawsuits.