You will be presented with a number of options before placing the image in your post.
Give the Image a title. By default it will use the file name, you can change it. You may add a caption that will appear below the image. Description too if you like, but not really needed.
You can choose to have the image link to something. This can be very handy if you want to upload a large image. You can have a smaller sized on inside your post but have it link to a larger version you’ve already uploaded to the server. Visitors can then click the link to view a full sized image without breaking the layout of your site.
You can set the alignment of the image and how text will wrap around it, or not wrap around it.
You may also set some size constraints here too. When you upload an image using the image uploader in WordPress it also creates a small thumbnail file of the image. So you may choose to display just the thumbnail in the post and have it link to the normal image. Or a medium sized version or the full sized file.
Now click the “Insert Into Post” button.