which word for the direction forward or backward?

[Learning_English]

I know we use word "sideway" if we want something to move in a direction to left or right. e.g. If you move sideways to left, I can watch the video clearly. I wonder which word we use if we want something to move in a direction forward or backward.
_________________
Please let me know if I have made any mistakes in any of my sentences.

[Yankee]

[Learning_English]

Thank you Yankee