Icons and Symbols
While working in CLion, you can see various icons all around the UI. For most of them, you can get a tooltip description by hovering the mouse over an icon, for example: 
This article gives a summary of icons that are not supplied with tooltips. Such icons belong to the following UI areas: Project View, Structure View, Breadcrumbs, or one of the Hierarchy Views (Call, Method, or Imports Hierarchy). 
Project View Icons
Folders and files | |
|---|---|
 | - Plain folder |
 | - Source folder |
 | - Excluded folder (highlighted with yellow background in the Project tree) |
 | - File marked as plain text |
 | - External library |
 | - Scratch files and consoles |
File types |
|---|
In the Project tree, files are marked with file type icons, for example |
, 
, 
(see 
indicates that CLion could not recognize the file type. Source files |
|---|
Files marked with blue overlay badges |
are source files (for CMake projects, if a file icon does not have this overlay badge, it means that the file is not included in VCS status indication |
|---|
If VCS integration is enabled for the project, CLion uses colors to denote VCS file status in the Project tool window. For the colors meaning, refer to File status highlights. |
Structure, Hierarchy, and Breadcrumbs Icons
Elements in Structure View, Call Hierarchy or Method Hierarchy can also have visibility indicators: private 
, protected 
, or public 
.
 | - Struct/Class |  | - Global variable |
 | - Struct/Class field |  | - Global constant variable |
 | - Struct/Class constant field |  | - Global static constant variable |
 | - Struct/Class static constant field |  | - Enumeration |
 | - Function |  | - Enumeration value |
 | - Pure virtual function |  | - Namespace |
 | - Constant function |  | - Union |
 | - Static function |  | - Typedef |