Model Representation

$m$: number of training examples
$x$: input variables / features
$y$: output variables / target variables
$(x,y)$: single training example
$(x_i,y_i)$: $i^{th}$ training example

Training set to learning algorithm to hypothesis $h$ (based on size of house) to estimates price

$h_\theta (x) = \theta_0 + \theta_1 x$
$\theta_i$: parameters

Linear regression in one variable = univariate linear regression