Hi All,

I have knowledge of different salesforce object relationships but can anyone give me better understanding with practical example among these different relationships. I might be wrong but I think we can also create junction object with lookup or master-detail but when should I use lookup and when should I use Master detail junction object? 

1. Lookup
2. Master-Detail
3. Self (Hierarchical)
4. Junction object using Lookup
5. Junction object using Master-Detail.