In 2002, Stewart Butterfield's project, Game Neverending, a massive multiplayer online game (MMO), failed to secure necessary financial support and was shut down. The game was meant to be an Inception-esque MMO but couldn't sustain itself.

In 2005, Yahoo! acquired the popular photo-sharing app Flickr for $35 million. Stewart Butterfield, co-founder of Slack, was part of the team that built Flickr and continued to work at Yahoo! as the General Manager and Senior Director of Project Management until 2008.

Slack was founded in the year 2009 with its headquarters in San Francisco, California, United States.

In 2010, Tiny Speck raised $5 million as part of its Series A round led by Accel Partners.

On the 27th of September 2011, Glitch was successfully launched by the Vancouver-based Tiny Speck.

On December 9, 2012, Tiny Speck announced the closure of the Glitch game, shifting its attention towards developing the Slack collaboration app.

In August 2013, Slack successfully onboarded 8,000 companies within a span of 24 hours, showcasing a rapid adoption rate.

On February 12, 2014, Slack officially transitions out of its Beta phase and adopts a Freemium model, marking a significant milestone in its evolution.

In April 2014, Tiny Speck secures a funding round of US$42.75 million for Slack, reporting 60,000 daily users and 15,000 paid seats at that time, indicating a strong investor interest and user base growth.

A captivating profile of Stewart Butterfield and his startup Slack was published, shedding light on the intriguing aspects of the company.

Slack acquires Spaces, a tool that enables collaborative document work remotely.

Slack secures $120 million in funding with a valuation of $1.2 billion, becoming the fastest-growing workplace software.

Slack announces the acquisition of Screenhero, a collaborative screen sharing app that allows users to speak to each other and access each other's screens for editing and more.

On February 5, 2015, Slack's co-founders were awarded the Crunchie for Founder of the Year by TechCrunch.

Slack announces 10,000 new daily active users signing up each week, with more than 60,000 teams and 135,000 paid accounts. The company claims it has 500,000 daily active users, having doubled twice in the last two quarters.

Slack confirms that their central user database was hacked over four days, leading to a compromise of some users' data. In response, the company implements two new security features: two-factor authentication and a team-wide password kill switch.

Slack raises $160 million in funding, with a post-money valuation of $2.8 billion. The platform is reported to be used daily by 750,000 workers.

Slack opened its European headquarters in Dublin, expanding its presence and hiring 100 people. The move added to the tech firms cluster in the capital.

A series detailing the evolution of Canada's modern tech companies, including Slack, from their beginnings to the present day.

Noah Weiss initiated Slack's Search, Learning, & Intelligence (SLI) Group in the new NYC office. This move aimed to enhance Slack's capabilities and services.

Slack opened a new office in NYC focusing on Search, Learning and Intelligence, with Noah Weiss leading the initiative.

Slack announces a successful funding round, raising US$200 million at a post-money valuation of US$3.8 billion.

Slack experienced a 90-minute outage leading to humorous reactions on Twitter, highlighting the impact of the platform's downtime on users.

IBM and Slack collaborate to integrate Watson's cognitive technology into Slack's tools and bots, aiming to benefit both companies. A plugin developed by IBM will provide Slack developers with access to the Watson Conversation API.

Microsoft announces the launch of Microsoft Teams, a software similar to Slack, offering workplace chat, meetings, notes, and attachments as an alternative.

Sisense, a business analytics software company, introduces bots for Slack, Skype, Facebook Messenger, and Telegram to enhance collaboration.

In a move to better integrate their services, Slack and Google announced a partnership in January 2017. The partnership aimed to bring new features and deeper integrations with Google services, including new bots for notifications and support for Team Drives.

On January 17, 2017, Slack announced an expansion of its office space. The details of the expansion were not specified in the provided information.

On January 18, 2017, Silicon Republic showcased the unveiling of Slack's impressive new offices in Dublin.

TechCrunch provided a virtual tour of Slack's newly opened office in New York City.

Design firm Snøhetta created minimalist office spaces for Slack in Lower Manhattan, focusing on simplicity and functionality.

Dezeen reported on February 1, 2017, about Slack's European headquarters opting for a unique design approach different from typical tech start-up offices.

Dropbox introduced an open-source Slack bot named Securitybot to address unauthorized access and security incidents in the workplace. The bot can automatically receive alerts from security monitoring tools and validate incidents with other employees.

Slack rolled out a feature that allows users to access in-message drop-down menus for apps, aiming to enhance connectivity with the necessary apps for work purposes.

Facebook announced its intention to provide a no-cost version of Workplace, its collaborative platform, as a competitor to Slack.

Slack, a San Francisco-based startup, expands its European presence by opening a new office in London, showcasing its commitment to the region despite Brexit uncertainties.

Slack establishes its presence in the UK by opening its first office in the country, marking its second office in Europe following its headquarters in Dublin.

In May 2017, Slack experienced a brief outage for some users as a result of a DDoS attack on its CDN provider.

In May 2017, Slack introduced screen sharing for video calls, a feature update stemming from the acquisition of Screenhero two years prior.

On June 13, 2017, Astro Technology integrated its AI-powered email bot with Slack and Alexa, allowing users to configure Astrobot to receive notifications about important messages.

Slack secures a $250 million funding round with SoftBank as the lead investor, valuing the company at $5.1 billion.

Many users face difficulties connecting to Slack as the company confirms and resolves a small 'connectivity blip'.

Slack receives a significant financing round from SoftBank, valuing the company at $5.1 billion, according to reports.

Slack raised $200 million at a valuation of $3.8 billion, showcasing its strong growth and investor confidence.

Slack, a collaboration software, reached a valuation of more than $1 billion within a year of its launch.

Slack acquired Screenhero to incorporate screen sharing and voice chat into its platform.

Slack has integrated IBM's Watson technology into its platform, enhancing its chatbot capabilities.

On October 6, 2017, Tiny Speck announced that they are now known as Slack Technologies, Inc. through a tweet on twitter.com.

Slack was recognized as the Company of the Year, gaining widespread attention and acclaim for its achievements and impact.

On October 31, 2017, Slack experienced a major outage, causing the messaging service to stop working worldwide. Users encountered a 'Server Error' when trying to access the platform.

Slack introduced new functionality, private shared channels, to enhance its service for businesses dealing with confidential information.

Slack collaborates with Workday to combine their expertise and improve employee communication and workflow.

Slack updated its privacy policy, allowing employers to download and read direct messages between co-workers without notifying them.

Slack announced that it has reached 8 million daily active users and 3 million paid users.

Slack launched Actions, a set of developer tools to streamline task completion within the platform. Integration with services like Asana, Jira, Pocket, and Zendesk allows users to perform actions directly from Slack messages.

Slack acquires the app Missions from Robots and Pencils, which helps automate routine processes in Slack.

On July 26, 2018, Atlassian announced the shutdown of its competing HipChat and Stride services, with intellectual property sold to Slack.

Slack acquires workplace chat app HipChat and its successor Stride from Atlassian, planning to shut down HipChat and migrate users to its own service.

In August 2018, Slack introduced an update to its status feature, enabling users to set expiration dates for statuses like commuting, meetings, and vacation. This enhancement allows for more flexibility and control over user statuses.

In September 2018, Slack completed the acquisition of Astro Technology, a San Francisco-based email management startup. The acquisition aimed to integrate chat and email functionalities within Slack, enhancing its communication capabilities.

Slack deactivates accounts and revokes free access for users related to countries embargoed by the United States, including Iran and North Korea, due to compliance with US regulations. Even visitors to these nations are affected by the ban triggered by geolocation updates.

Slack announces that they have surpassed 10 million daily active users, showing significant growth from 8 million in May 2018. The platform is used by over 85,000 organizations to facilitate communication among employees.

Slack confidentially applies with the U.S. Securities and Exchange Commission to list shares publicly, indicating a step towards becoming a publicly traded company.

Mattermost, a private and open-source competitor to Slack, secures $20 million in Series A Funding for its workplace chat app. It is recognized as the fastest-growing messaging platform for engineering teams in large organizations.

Slack releases a dark mode feature in the latest app update for iOS and Android, fulfilling one of the most requested features by users.

Slack announces the removal of 28 accounts linked to known hate groups, following leaked messages from a neo-Nazi organization planning activities promoting white racial consciousness.

On April 26, 2019, Slack reported more than 10 million daily active users from over 600,000 organizations in more than 150 countries.

On June 20, 2019, Slack Technologies made its debut on the New York Stock Exchange through a direct stock listing.

In August 2019, Slack launched new features such as admin workflow automation and announcement channels to cater to larger organizations. These updates allow administrators to control how employees communicate and ensure important information is effectively shared.

In September 2019, Slack rolled out dark mode for desktop users on Windows, macOS, and Linux. This feature provides users with a different visual experience and can be easier on the eyes, especially during late hours.

Slack introduced Actions feature to streamline task creation and completion within the platform.

Slack achieved a milestone of 8 million daily active users, out of which 3 million are paid subscribers.

Slack submitted documents to go public and disclosed financial figures showing losses and revenue.

Slack introduced new administrative features tailored for bigger organizations to enhance their user experience and management capabilities.

On October 20, 2019, an article provided an overview of Slack, covering its history, funding, integrations, and direct listing.

On November 13, 2019, Slack announced the formation of its partner channel as part of its focus on enterprise clients.

On February 10, 2020, it was reported that IBM would deploy Slack to all of its 350,000 employees, becoming Slack's largest client.

On November 25, 2020, the Wall Street Journal reported that Salesforce was in advanced talks to acquire Slack, with the deal closing in 2021 for $27.1 billion.

Salesforce announced its acquisition of Slack for $27.7 billion on December 1, 2020, solidifying a major deal in the tech industry.

On December 3, 2020, Microsoft dealt a significant blow to Slack, possibly indicating a shift in the competition between the two tech giants.

On January 4, 2021, Slack experienced a significant outage lasting several hours, affecting core features like messaging and calls.

Salesforce completed the acquisition of Slack in a massive $27.7 billion deal, reshaping the landscape of enterprise software and communication platforms.

On April 14, 2021, a comparison between Slack, Microsoft Teams, and Google Meet was observed on Google Trends, reflecting the popularity and interest in these communication platforms.

On April 26, 2021, there was an indication of interest in Microsoft Teams, Slack, and Google Meet, possibly showing the relevance and usage of these communication tools.

The acquisition of Slack by Salesforce was finalized on July 21, 2021, marking a significant milestone in the tech business landscape.

On September 20, 2021, the Ninth Circuit issued a split decision, ultimately overturned, affirming the district court's ruling in the case. The dissent focused on the strict liability for issuers in Sections 11 and 12(a)(2) of the Securities Act of 1933.

On December 5, 2022, Stewart Butterfield left Slack, and Lidiane Jones took over as CEO, followed by Denise Dresser in November 2023.

On December 31, 2022, Slack reported the compromise of its private GitHub repositories due to stolen security tokens.

In March 2023, Salesforce announced a partnership with OpenAI to launch a ChatGPT integration for Slack, enabling users to summarize conversations, answer questions, and draft replies using AI technology.