A computer system comprising: one or more processors; and one or more computer-readable media having stored thereon instructions that are executable by the one or more processors to configure the computer system to receive user input, including instructions that are executable to configure the computer system to perform at least the following: displaying a set of characters arranged sequentially in a curvilinear or linear fashion such that any one of the characters in the set of characters can be identified for selection by substantially continuous and uniform user input from a user, wherein each given character in the set of characters is displayed at a level of prominence determined by and proportional to a probability that the given character is a next selected character based on a string of characters previously selected by the user; receiving user input in a substantially continuous and uniform fashion from the user to identify a character in the set of characters; receiving user input selecting the identified character; and adding the selected character to the string of characters; characterised in that said displaying comprises displaying the set of characters in each of a first layer and one or more adjacently ordered layers, wherein, in the one or more adjacently ordered layers, the probability used to determine the level of prominence of a given character is further based on one or more characters identified in previous layers, and wherein the one or more adjacently ordered layers are moved along with character identification in the first layer so that the most prominently displayed character in each of the one or more adjacently ordered layers is identified for selection. one or more processors; and one or more computer-readable media having stored thereon instructions that are executable by the one or more processors to configure the computer system to receive user input, including instructions that are executable to configure the computer system to perform at least the following: displaying a set of characters arranged sequentially in a curvilinear or linear fashion such that any one of the characters in the set of characters can be identified for selection by substantially continuous and uniform user input from a user, wherein each given character in the set of characters is displayed at a level of prominence determined by and proportional to a probability that the given character is a next selected character based on a string of characters previously selected by the user; receiving user input in a substantially continuous and uniform fashion from the user to identify a character in the set of characters; receiving user input selecting the identified character; and adding the selected character to the string of characters; displaying a set of characters arranged sequentially in a curvilinear or linear fashion such that any one of the characters in the set of characters can be identified for selection by substantially continuous and uniform user input from a user, wherein each given character in the set of characters is displayed at a level of prominence determined by and proportional to a probability that the given character is a next selected character based on a string of characters previously selected by the user; receiving user input in a substantially continuous and uniform fashion from the user to identify a character in the set of characters; receiving user input selecting the identified character; and adding the selected character to the string of characters; characterised in that said displaying comprises displaying the set of characters in each of a first layer and one or more adjacently ordered layers, wherein, in the one or more adjacently ordered layers, the probability used to determine the level of prominence of a given character is further based on one or more characters identified in previous layers, and wherein the one or more adjacently ordered layers are moved along with character identification in the first layer so that the most prominently displayed character in each of the one or more adjacently ordered layers is identified for selection.