On the left side of the screen you'll find the Explorer, in which you can see all the components of your project, e.g. documents, codes or memos.
In the upper part of the screen, you'll see the different tabs with all the menu options.
The six main entity types in ATLAS.ti are: Documents, Quotations, Codes, Memos, Networks, and Links. All entity types have their own manager, which can be opened from the Home tab:
(Nederlandstalige Library Guide ATLAS.ti)