Internal Ribosome Entry Sites (IRES)

I wanted to know if an IRES was a linear sequence or an mRNA secondary structure. Technically, I should have assumed that a linear sequence might lead to a secondary structure (based on the laws of protein assembly) but I didn't. I looked it up:

IRES elements are highly structured cis-acting regions on the viral RNA. They serve as binding sites for proteins of the translational apparatus and facilitate the internal entry of ribosomes independently of the 5´-end of the viral RNA or a cap-nucleotide.

So this one mRNA was like, "you don't have to recognize my cap to sit down" and the ribosome was all like, "okay." Together, they made a completely different protein...