Howdy folks, I’m a few weeks into learning Bass now.
I’m trying to figure out how you know how many BPM a song is supposed to be in?
I’ve seen tracks that are 4/4 be 100bpm, 120bpm, 85bpm.
I just finished Module 5. Maybe its coming up in the next modules?
In the course extra’s PDF I see that those tracks are marked off how many bpm.
Confused … please help
Welcome, @digbit!
BPMs are measure of how “fast” a song is supposed to be played. The beats in the name usually refer to quarter notes (unless otherwise specified). Thus, 100 BPM means that per minute 100 quarter notes should be played. In that sense, 120 BPM is faster (more quarter notes per minute) than 100 BPM, while 80 BPM is slower.
As a reference: 60 BPM is one quarter note per second, 60 per minute - rather a moderate tempo.
Metronomes can be set to a certain BPM value to give you the speed of a song.
I hope this is what you were wondering about!? 
I understand what you’re staying but in my current noob state that doesn’t help me too much. I currently practice with a metronome.
If I wanted to play Come as you are from Nirvana using the 50 first bass book. As an example. How am I supposed to know that track would be 60, 80, 100… bpm so i can set my metronome up?
Ah, OK, I see…
I don’t have that book handy right now, but often (good) sheet music gives the BPM somewhere in the top left corner of the first page, like in this example of Pat Metheny’s “Lakes”:
If that info is missing, you can play a recording of “Come as you are” and switch on the metronome (I take it it is an app on your phone, and not the old-fashioned kind!?!?) and use the “tap” function to tap along the song (the beats of the song). Then, the app will tell you how many BPMs that is, after which you go from “tap” mode to “metronome” mode, set it to that BPM and get practicing 
Or… you can “ask” the internet, which claims “Come as you are” should be played at 120 BPM.
ah see that makes more sense because its indicated on the sheet music. That’s what’s used in the Course Extra’s PDF as well.
I don’t see any reference of that in the book for any of the 50 songs.
Ah, OK, no numerical value is given, but it does say “moderately”…
Of course, that presumes some knowledge of what “moderately” usually refers to in terms of tempo. This is something much more common in classical music.
Again, the internet to the rescue:
If you scroll a bit down in the article, you’ll find the classical tempi translated to bpms or bpm ranges!
@joergkutter thanks dude that’s helpful.
All the tracks are marked off using that.
Enjoy your isolation! Thanks for your quick responses.
You’re welcome!
A good time to practice 
A tap tempo metronome is a worthwhile investment!!
download the soundbrenner for your phone, always in your pocket
You can also listen to the song while looking at a stopwatch to figure out how fast it is. Just count the number of beats in 15 seconds and multiply by 4. Like taking your pulse!
That is one of the reasons I have never used that book. I tossed it in a dark corner of my office closet as soon as I saw it was only in tab, with no musical notation, no reference to time signature, etc.
