1. Linezolid is an antibiotic used for the treatment of infections caused by Gram-positive bacteria that are resistant to other antibiotics. Linezolid is active against most Gram-positive bacteria that cause disease, including streptococci, vancomycin-resistant enterococci (VRE), and methicillin-resistantStaphylococcus aureus (MRSA). 

2. The main uses are infections of the skin and pneumonia although it may be used for a variety of other infections including drug resistant tuberculosis. It is used either by injection into a vein or by mouth. Linezolid is a member of the oxazolidinone class of medications. 
  
3. As a protein synthesis inhibitor, it affects the ability of bacteria to produce protein. This either stops growth or results in bacterial death. Although many antibiotics work this way, the exact mechanism of action of linezolid appears to be unique in that it blocks the start of protein production, rather than one of the later steps. As of 2014 bacterial resistance to linezolid has remained low.