Classes declared in a report will be aliases as LCL_, this means their usage will only be local to this report
Classes declared as global will be aliases as Z|YCL_, this means their usage isn't restrict to a specific report. The global classes declared in SE24 are reusable.
Signature of methods are to be named conventionally as follow:
- IX_<name> for IMPORTING parameters
- EX_<name> for EXPORTING parameters
- CX_<name> for CHANGING parameters
- RX_<name> for RETURNING parameters
X is for the type of parameters
- V for variable
- S for structure/work-area
- T for table
- O for object
https://github.com/SAP/styleguides/blob/master/clean-abap/CleanABAP.md