Referencing a channel within a conversation

To create a clickable reference to a channel in a Slack conversation, just type # followed by the channel name. For example: #general.

To grab a link to a channel through the Slack UI

To share the channel URL externally, you can grab its link by control-clicking (Mac) or right-clicking (Windows) on the channel name:

The link would look like this:

Note that this link doesn't change even if you change the name of the channel. So, it is better to use this link rather than the one based on channel's name.

To compose a URL for a channel based on channel name

Opening the above URL from a browser would launch the Slack client (if available) or open the slack channel on the browser itself.

To compose a URL for a direct message (DM) channel to a user

Sure you can:

for example: (of course that for accessing it, you must be part of the team)

You can use

slack://

in order to open the Slack desktop application. For example, on mac, I've run:

open slack://

from the terminal and it opens the Mac desktop Slack application. Still, I didn't figure out the URL that should be used for opening a certain team, channel or message.

This link opens the channel in the browser

This link opens up the slack channel in the App

When I tried yorammi's solution I was taken to Slack, but not the channel I specified.

I had better luck with:

and

Although, they were both still displayed in a browser window and not the app.