You can add text to a composition using text layers. Text layers are useful for many purposes, including animated titles, lower thirds, credit rolls, and dynamic typography.
For a video tutorial on animating text, go to the Adobe website.
You can animate the properties of entire text layers or the properties of individual characters, such as color, size, and position. You animate text using text animator properties and selectors. 3D text layers can optionally contain 3D sublayers, one for each character. (See Animate text with text animators and Per-character 3D text properties.)
Text layers are synthetic layers, meaning that a text layer does not use a footage item as its source—though you can convert text information from some footage items into text layers. Text layers are also vector layers. As with shape layers and other vector layers, text layers are always continuously rasterized, so when you scale the layer or resize the text, it retains crisp, resolution-independent edges. You cannot open a text layer in its own Layer panel, but you can work with text layers in the Composition panel.
After Effects uses two kinds of text: point text and paragraph text. Point text is useful for entering a single word or a line of characters; paragraph text is useful for entering and formatting the text as one or more paragraphs.