Would be useful for the article to start with a word on what memory ordering is.

Edit: it means, (re)ordering of memory access operations esp. when multiple execution units (cores) operate in parallel. Weakly ordered (ARM, RISC-V): if Core 1 writes Memory 1 then Memory 2, but for some reason writing into Memory 2 is quicker, then Core 2 may see Memory2 written before Memory 1 is written. While strong ordering (x86) retains the original order.