New User: Library question

Hello. I am using Mac OS X Version 10.5.8 with Audacity 2.0.5.
I am new to audio editing and when I was reading the manual for Audacity, it said that to export as mp3, I had to download Lame or FFMpeg. However, before downloading either I tried to export as mp3 and Audacity allowed me to. When I checked the exported mp3 on vlc media player, everything worked fine. Why is it that I did not have to download either of the aforementioned libraries to do this?
Thank you

You only need Lame for mp3, but ffmpeg can do mp3 export too, if Lame is installed.

Probably you could export mp3 from Audacity because Lame was already installed by some other software and it was a version that’s compatible with Audacity?

Maybe with “iTunes-LAME Encoder”?

I think I know what happened. I originally installed an old version of Audacity (1.2.6a because my computer is older) along with Lame. Lame could not be found by this Audacity version, so I deleted Audacity, Lame, and all associated files so I could start fresh. I downloaded a newer Audacity (2.0.5) which exported fine as mp3. I must have done something wrong when I tried to delete Lame. I was having trouble with it since Audacity could not find it and I had to download and delete Lame twice, so maybe I accidentally put the Lame file elsewhere during the processes.
Anyway, according to Audacity Preferences, it is now finding Lame in location /usr/local/lib/audacity/libmp3lame.dylib. The strange thing now is that when I look for this location in Finder, I cannot locate it, but Audacity says it is there.

Thank you for your help.

So long as Audacity can find it and use it, that’s good enough.
As a newcomer to Mac OS X, I’m astounded by how bad the included file browser (“Finder”) is, so I’d not worry that “Finder” can’t find it.

I’ve done some more research and found that /usr is a hidden folder on Macs inaccessible through a standard Finder search. I had to go to the Finder menu in the upper left part of the screen, click Go, click Go to Folder, then type in the location: /usr/local/lib/audacity/libmp3lame.dylib. A new folder appears in Finder that is the /usr folder and that is where Lame was sent to. At least I know where it is and that Audacity has access to it.
I learn something new about Mac every day.
Thank you again for your prompt responses.

Finder (Spotlight) search excludes system files by default. I wouldn’t advise to change the default, as it will become quite slow.

If you need to explore the innards of OSX, you need to learn the Terminal, where none of this idiot-proofing exists.

The Finder has always been the weakest part of OSX. It has gotten a little better lately. It’s now possible to open a folder with 10.000 + files in it, fi.

There are however a number of background processes that average users find useful, such as Spotlight indexing, Data Detectors or custom icons. Power users don’t want or need most of these, but it simply isn’t possible to turn them off without getting into a whole lot of trouble. And personally, I wouldn’t want to miss Data Detectors, as it opens most data files in the appropriate default app when double clicking and enables Finder preview, without opening an app. There is no default prefspane to set it in System preferences, but there is a 3rd party one, RCDefaultApp: