Mount Hood is a stratovolcano, meaning it is a tall, cone-shaped volcano built up by layers of lava flows, ash, and tephra. This makes it capable of a variety of eruption types, but the most common and historically documented are:

* Explosive eruptions: These involve the rapid release of gas and ash, creating pyroclastic flows and ash plumes that can travel long distances.

* Effusive eruptions: These involve the slow and steady flow of lava, which can create lava flows and domes.

While Mount Hood has erupted explosively in the past, its recent activity has been dominated by effusive eruptions, most notably the formation of lava domes around its summit.

Here are some further details:

* Past eruptions: Mount Hood has erupted at least nine times in the past 1,500 years, with the most recent eruption occurring around 1781-1782. These eruptions have ranged in intensity from small, effusive events to larger, explosive eruptions.

* Potential future eruptions: While Mount Hood is considered active, it is not currently showing any signs of imminent eruption. However, the possibility of future eruptions, both explosive and effusive, cannot be ruled out.

It's important to note that the type of eruption can vary, even within the same volcano, and predicting the exact type of eruption is difficult.