Slack

Slack is a team communication client that arranges conversations into channels, each focused on a project, team or topic. The Windows desktop app is a free download and connects to one or more workspaces, letting you switch between an employer's grid and a community or client workspace without opening several browser tabs. The free plan is genuinely usable for small teams, with message history and app limits that matter mainly at scale.

What it does

Channels keep discussion searchable and organised, and threads pull side conversations out of the main flow so a channel stays readable. Direct messages and group messages cover private exchanges. Huddles are lightweight audio or video calls that can start inside any channel or DM, with screen sharing, and they stay open for others to drop into. Files, images and documents can be dropped into any conversation, with a search index that covers both messages and the content of many uploaded file types. Hundreds of integrations connect Slack to calendars, code repositories, ticketing systems and CI pipelines, and workflows can automate routine handoffs through no-code builders.

The workflow

Install the client, sign in to a workspace with an email address, and accept the invitation if one was sent. The window then shows a workspace rail on the left, a channel sidebar, and the active conversation with a message box that supports markdown-style formatting, slash commands and drag-and-drop attachments. Settings cover notification schedules, a do-not-disturb window, keyword highlights, and per-channel mute controls, all of which matter once you join more than a couple of busy channels. Keyboard shortcuts cover quick switcher navigation, and the sidebar can be reordered or grouped into sections.

Practical settings and limits

Slack is proprietary, cloud-hosted software, so there is no self-hosted option and message data lives on Slack's servers. The free plan limits how far back you can scroll and how many apps or integrations a workspace can add; voice and video features also have participant caps that differ by plan. Because a workspace is a shared social space, notification volume can climb quickly, and the desktop client keeps several helper processes running, which costs memory on older machines. Search covers everything you have access to, which is convenient but also means administrators can export and review workspace content.

Who should choose something else

If you need end-to-end encryption, self-hosting, or full history without paying, an open-source team chat platform is the better answer. Teams whose work already lives inside a productivity suite may prefer that suite's bundled chat to avoid another account and another notification stream. Anyone looking for community-scale voice channels with roles and moderation should consider a community-oriented platform instead of a workplace messenger.