Hi, Joseph —

Thanks for the question.

Let me answer your question a few different ways.

This posting from our knowledge base will give you a good idea of what some of the vestments are and why the color of the vestments are, what they are:

• Why are the vestments of the Catholic clergy so elaborate and do the have some significance?

When in choir dress, a Latin-rite cardinal wears scarlet garments — the blood-like red symbolizes a cardinal's willingness to die for his faith like the martyr's did.

I found this piece on EWTN, which all would agree is a trusted source:

• The color of sacred vestments Rome, December 7, 2004
  

This page on Wikipedia will give you a historical outline of what colors were used when:

• On Wikipedia — Liturgical colours

This page will list the various vestments worn by some major Christian faiths and the rubrics for vesting. Rubrics deal with the rules governing the celebration of the Mass, for priests with valid Holy Orders, and for Protestant ministers for non-Catholic Christian services.

• On Wikipedia — Vestment

Currently:

• Red symbolizes martyrdom; like when the priest celebrates the Mass on the feast day
  of a martyr.
  
• Shades of red fall into this category and are usually long standing customs
• Black symbolizes mortification of one's soul. (This is why some priests wear black.)
• Violet symbolizes the penance we should be doing for those who have passed on to eternal judgment, and is also used during the Penitential season of Lent.
• White represents purity and is used on the Solemnity of the Resurrection and Feasts of Our Lady.
  

None of the colors represent any ranking that I am aware of.

Hope this answers your question.

Mike