When we talk about working with arrays in data structures, there are some important actions we need to know about. Here’s a simple guide to these key operations:

1. Insertion: This means adding a new item in a certain spot in the array. Depending on where you want to insert it—at the start, the end, or somewhere in the middle—the difficulty can change. For example, putting an item at the end of the array is usually very easy if there’s space. This is called an $O(1)$ operation. But if you want to add something at the beginning, you might need to move some items around, which can take longer, usually $O(n)$.

2. Deletion: This is about removing an item from the array. Like insertion, it can be simple or tricky based on where the item is located. If you need to shift things around when deleting an item, expect it to take $O(n)$ time.

3. Traversal: This means going through each item in the array one by one. You do this to get values or to do things like searching for an item or printing what’s there. Traversal usually takes $O(n)$ time because you check each item.

4. Search: Finding an item in the array is very important. If the array is organized in order, you can use a method called binary search, which is quick and takes $O(\log n)$ time. If it's not organized, you would use linear search, which typically takes $O(n)$.

5. Update: Changing an item that’s already in the array is fast and easy. This usually takes $O(1)$ time, since you can go straight to the item through its index.

These basic operations help us understand how to work with arrays better and prepare us for more complex data structures in the future.