Four groups, around forty tools, and how to find the one you want without hunting.
The four groups
Inside a project the sidebar is grouped the way the business is: Project Management holds the day-to-day communication tools, Contract Management holds the commercial ones, Quality and Safety holds the compliance record, and Resource Management holds the programme, the plant and the people. The grouping is not cosmetic: tools in the same group tend to feed each other.
Two levels, two sidebars
Step up out of a project into your organisation's workspace and the sidebar changes. Some names appear at both levels, Directory, Documents, Whiteboard, Equipment, Permits and Method statements among them, and they are genuinely different registers rather than two views of one. An organisation-level document is your company's; a project document belongs to that job.
The top of the list
Above the groups sit the two screens you will open most: the project dashboard, and My Items, which carries a badge counting what is actually waiting on your action. If you only ever learn two places to click, make it those.
Finding a tool
The sidebar collapses to an icon rail if you want the width back, and global search finds a tool by name as readily as it finds a record. If a tool you expect is missing, it is either switched off for this project in the tools catalogue, or your permission template does not include it.