The Basics

Malaysians can skip this part and go to Part 2: Prepping for the One Year War

What is SPM?

The Sijil Pelajaran Malaysia (SPM), or the Malaysian Certificate of Education, is a national examination taken by all fifth-year secondary school students in Malaysia.

Equivalents:
O-Level
General Certificate of Secondary Education(GCSE)
11th grade in American's K–12 (education)

What is a compulsory pass subject?

It refers to subjects which all SPM candidates have to pass. If a student fails a compulsory pass subject, he/she is considered to have failed SPM. Students can choose to retake these subjects during the SPM Ulangan if they failed it.

Compulsory pass subjects

Bahasa Melayu(BM)

Sejarah(SJ)

What is a core/compulsory subject?

It refers a subject that must be taken by all SPM candidates. The only exceptions are Pendidikan Moral & Pendidikan Islam which depends on the students' religion and Science which is only compulsory for students in the Commerce, and Literature and Arts streams.

Core/compulsory subjects

Code	Subject (Official name)	Subject (English name)	Examination language
1103	Bahasa Melayu	Malay language	Malay
1119	Bahasa Inggeris	English language	English
1223	Pendidikan Islam (For all Muslim students)	Islamic Studies	Malay
1225	Pendidikan Moral (For all Non-Muslim students)	Moral Studies (also Moral Education)	Malay
1249	Sejarah	History	Malay
1449	Mathematics	Mathematics	English and Malay
1511	Science (For students in the Commerce, and Literature and Arts streams only)	Science	English and Malay

More detailed explanation- https://en.wikipedia.org/wiki/Sijil_Pelajaran_Malaysia