ADAPL is a general-purpose programming language that incorporates an Axiell Collections database record interface. An ADAPL program (also called an "adapl") can either be executed as a stand-alone program or be used during various database functions in Collections, e.g. to validate data entry, to perform extra actions when a record is saved, to create printable output or to carry out an extra check during deletion, etc.

If an ADAPL program is run from within a Collections application, all data in the current record will be available for manipulation.

ADAPL programs can be used to modify or validate Collections data or to generate data output routines. Adapls can also be used to start external programs or routines from within a Collections application.

An ADAPL program is created as an ASCII text file with the extension .ada. You can do this in any text editor. After writing the code you must compile the program with the ADAPL compiler to make the code ready for execution.
You can edit existing adapls in Designer as well: just click an adapl in the tree view in the Application browser to open it, and right-click the ADAPL code to open a pop-up menu with the options to save your changes or to compile the file (to the same folder).

Note that when an .ada source file is saved/converted to Unicode in UTF8 encoding, a UTF header of three characters is added to the beginning of that file. That first line of adapls often contains an asterisk, to indicate comments. So after conversion, the first line contains the UTF8 header followed by an asterisk.