RCMasterAA said:
And slightly more important for all those mark lovers.
Tutorial: no marks awarded (unless there's a test during a tutorial time or attendence)
Lucture: no marks awarded
Laboratory: marks given for both attendence and work done
Although this is generally correct, there are exceptions. For example, accounting has homework checks once in a while, some has attendance marks, and some has "participation" marks such as comp1091 (discontinued course). There's even a lecturer who marks attendance(which is rare in general though).
So you should, as a minimum attend all tutorials and labs. lectures could usually be skipped(without affecting grades directly, unless there's a test on)