To find the number of possible combinations for the bike lock, we can use the principle of multiplication.

The lock has 4 digits, and each digit can be any of the digits from 0 to 5, which means there are 6 possible choices for each digit.

So, the total number of possible combinations is calculated as:

$6 \times 6 \times 6 \times 6 = 6^4$

Now, let's compute this:

$6^4 = 1296$

Thus, there are 1,296 possible combinations for the bike lock.

Would you like more details or have any questions? Here are some related topics:

1. How would the number of combinations change if the lock had 5 digits?
2. What if the digits could be any number from 0 to 9 instead?
3. How many combinations would there be if repetition of digits wasn't allowed?
4. Can we use this method for combinations in real-life scenarios like pin codes?
5. What is the probability of guessing the correct combination on the first try?
6. How does the combination count change with different base numbers?
7. Can you explain the difference between permutations and combinations?
8. What is the general formula for finding the number of combinations with n digits and k possible values per digit?

Tip: Remember, when solving combinatorial problems, determining whether the order matters is crucial!