A PowerPoint (more accurately, the power outlet you plug a PowerPoint presentation device into) provides AC (Alternating Current).
Power outlets, in general, supply alternating current (AC). In many regions, this is between 220-240V AC at 50 Hz. This AC power then gets converted by the device's power adapter (if applicable) into the appropriate voltage and current (which may be DC - Direct Current) needed by the device itself.
Therefore, the power outlet (what you'd plug a "PowerPoint presentation device" into) provides AC. The device plugged into that outlet may use either AC or DC, converted from the AC supplied by the outlet.
