how to take away the legend of a ggplot code example

Example 1: ggplot2 remove legend

### Three options (where p is the plot object)

# Remove the legend title: 
p + theme(legend. title = element_blank())

# Hide the entire legend to create a ggplot with no legend. 
p + theme(legend. position = "none") 

# Hide legend for a specific geometry, say geom_text(). 
p + geom_text(show.legend = FALSE)

Example 2: labs fill ggplot2

df <- data.frame(x=1:10,group=c(rep("a",5),rep("b",5)))

legend_title <- "OMG My Title"

ggplot(df, aes(x=x, fill=group)) + geom_density(alpha=.3) +   
    scale_fill_manual(legend_title,values=c("orange","red"))