Explain the meaning of standard codes GB/T, JB/T, SH, ASTM, ASME, ANST, BS, JIS?

GB/T: National Recommended Standards
JB/T: Recommended Standards for Machinery Industry
SH: Sinopec Standards
ASTM: American Society for Testing and Materials
ASME: American Society of Mechanical Engineers
ANST: American National Standard
BS: British National Standards