Within the modern Digital Audio Workstation the Editing capabilities are amazing. The audio waveform can be manipulated in countless ways. We can start with tools to cut, copy, paste which allows you to move your audio anywhere you want. This can be useful for repairing mistakes, as you can grab a good piece of audio and copy and paste it over the bad take. Playlists in Pro Tools are a great way to comp multiple takes into one good solid take. You can search down through your takes  and highlight a section click the arrow and pull it into your comp take. A very powerful  tool for getting the best out of your recorded audio.  Fade ins and fade outs as well as cross fades can smooth out your track as well. Pro Tools offers Beat Detective and Elastic audio. Beat Detective is great for Editing a multi track drum take lining up all the beats to the grid for a spot on take that is dead on with the click. Elastic Audio allows the audio to be stretched  without  altering the pitch, so you can literally speed up or slow down an entire song. Within Pro Tools if you have recorded to a click and you are in grid mode you can move whole sections of your song to try different arrangements. There are also tools for duplicating, reversing, consolidating and adjusting gain levels. Editing digital audio is an essential part of manipulating modern music.