I need to keep records about my newly learnt things.
Basically I need to write more lines in that record book, like codes, links and such things. So can you tell me if there any app like that or if not are there any online resource?
You can try Rednotebook. This is a software that allows to write a journal on a daily basis. You also can include pictures and formatted code.
If you store the data file on a remote site, it is possible to sync.