Both Slack and HipChat create an activity feed that archives uploads in chronological order, as well as by channel and user, which makes files very easy to access. Slack lets you narrow down your word search by file type and messages. Slack also has a personal feed that allows you to see messages and files that you’ve personally uploaded or starred.
Similarly, HipChat allows you to search through all files and links shared within a specific room or perform a word search targeting a specific room or user. However in Slack you can see the text before and after the result thus allowing you to more accurately make a decision. As a bonus in Slack search when you jump to your result it will scroll you to where it found it.
Both Slack and HipChat allow you to preview image and gif files, whether they be files you uploaded or links you’ve posted. Additionally, Slack allows users to easily request feedback from the rest of the team and receive comments on specific files within their respective channels, which can later be easily accessed directly on the attachment. This feature is not available on HipChat yet. This is probably the main major difference between the two applications. In the real world we end up posting meeting notes and we can add comments specifically to those notes as well as share the post into other channels as necessary.