What is eSIM?
eSIM means embedded SIM card. There are no physical SIM cards involved and no physical swapping over required by you. However, not all Telco support eSIM. Lucky for us in Malaysia, most major telcos like Maxis, Celcom, Digi and Yoodo support eSIM.
Since it's embedded in mobile phone itself, you don't have to pull out the SIM card slot to change SIM card. However, recent phones that has eSIM enabled still retain SIM card slot because not all every telco in other countries can support eSIM yet.