STDs/STIs: Frequently Asked Questions

What's the difference between STD and STI?
How are STDs spread?
I just found out the person I had sex with has a sexually transmitted infection (STI). What should I do?
I have vaginal itch, burn, smell or a genital bump. Can you help me?
How many STDs are there?
Do you test and treat both women and men?
How much do you charge for STD testing?
When will I get the results of my STD test?
Where can I find out more information on STDs/STIs?