how to answer HLD and LLD

Question

I have recently attended Amazon Interview and got rejected after design round, its happened three times with Amazon in 2 year, i always getting rejected because of design round. please help me to know how should i answer an design question. questions like 1) design elevator control system 2) design whisper-sync feature (used in Amazon instant video platform) they ask me to design End to end HLD LLD i did not get what exactly differ in both, i explain as a algorithm wise, but could not properly by HLD and LLD.

i mean i searched alot, but could not found a way to answer such question.

Any help will be good for me.

Thanks,

Answer 1

HLD: High Level Design consist of sub-system design to define. It target architect, Technical leads etc. - Solution Technical Overview - interfaces - primary classes - Database entities with - Assumptions

LLD: Lower level design consist of individual module/section design for the sub-system. It primarily extension of HLD. It targets core developers & covers following items: - All classes entities & interfaces - DB Model (Tables, column attributes, indexes, constraints) - Algorithms for methods used in classes - Logging implementation

I hope it helps!!