When describing the strength of metals, I notice people tend to talk all puffed up about a number they put before the metal. Like saying it is 6160 Aluminum or 6061 and the like. Other metals I have heard described were in the 3000 range or so. What do these numbers really mean? When I ask people after they say such a number, they usually look blankly for a while and then just say, “it means it is strong.” or some equal nonsense.
I believe in the case of aluminum, the numbers you refer to are the alloy designation. You may be interested in the information about these designators given here, http://www.secat.net/tech%20alum%20designations%20121202.php
chukhung has it right: the numbers describing metals (6061 aluminum, for instance) have nothing to do with strength, per se, but simply designate the alloy used. However, certain alloys are in general stronger than others, and aluminum often has a temper designation (6061-T6, for instance), where the tempering process may give an increase in strength (quick overview of aluminum alloy/temper designations). You can’t really tell what the strength is from the alloy designation, though, except by knowing ahead of time which alloys and/or tempers are strongest. Alloy numbers themselves do not correspond to strength (so 6000 series aluminums are not three times stronger than 2000 series aluminums).
Alloy designations exist for other metals, such as steel and copper alloys, among others. Here’s a nifty overview of metals: more than you wanted to know.
If the people you’re talking to are describing the strength of the material with the alloy designation, then you’ve correctly surmised that they don’t know what they’re talking about.