Straight-line amortization records the same amount of interest expense in each period until the bond matures.  The effective-interest method records interest expense based on the carrying value of the bond and the amount of interest paid.  Both methods record the same amount of interest over the term of the bond.  However, the difference is in how much is recorded each period and how it is calculated. In the United States, the straight-line amortization method is permitted under SEC-approved rules known as Generally Accepted Accounting Principles (GAAP). Elsewhere the effective interest method may be required in accordance with International Financial Reporting Standards (IFRS). The straight-line method of amortization records the same amount of interest expense in each interest period.  For each period until the bond matures, the balance in discount and bonds payable will decrease by the same amount until it has a zero balance.  Using this method, by the time the bond matures, the carrying value will be equal to the face value.  For example, suppose a company sold $200,000, 5-year, 10% bonds for $198,000. The $2,000 bond discount ($200,000 - $198,000) amortization is $400 ($2,000/5) for each of the five amortization periods. This is similar to straight-line amortization of bond discounts.  Over the term of the bond, the balance in premium on bonds payable decreases by the same amount each period.  By the time the bond matures, the balance in premium in bonds payable is zero, and the carrying value equals the face value of the bond.  For example, suppose a company sold $200,000 bond for $202,000.  This results in a bond premium of $2,000 ($200,000 - $202,000). The premium amortization for each interest period is $400 ($2,000/5). The effective interest rate is the percentage of carrying value over the life of the bond.  It is established when the bond is issued and remains constant in each period.  For this method, the interest expenses recorded equals the constant percentage of the carrying value of the bond....

TL;DR in Indonesian:
Ketahuilah perbedaan amortisasi metode garis lurus dengan metode bunga efektif. Pahamilah amortisasi diskonto obligasi dengan metode garis lurus. Pahami amortisasi premi obligasi dengan metode garis lurus. Pahamilah amortisasi premi atau diskonto dengan metode bunga efektif.