diff --git a/doc/syntax.md b/doc/syntax.md
index 5d6acbb..595a110 100644
--- a/doc/syntax.md
+++ b/doc/syntax.md
@@ -71,7 +71,7 @@ _instruction
     value
     assign
     integer
-    float
+    real
     string
     array
     add
@@ -102,9 +102,9 @@ integer
     "<integer value=" tag "/>"
     "<integer>" instruction "</integer>"
 
-float
-    "<float value=" tag "/>"
-    "<float>" instruction "</float>"
+real
+    "<real value=" tag "/>"
+    "<real>" instruction "</real>"
 
 string
     "<string value=" tag "/>"
diff --git a/sample/stl.pl.xml b/sample/stl.pl.xml
index 4bee69a..8ba8597 100644
--- a/sample/stl.pl.xml
+++ b/sample/stl.pl.xml
@@ -7,14 +7,14 @@
         </call>
         <assign variable="arr">
             <array>
-                <float value="0.1" />
+                <real value="0.1" />
             </array>
         </assign>
         <call function="array-set">
             <arguments>
                 <value variable="arr" />
                 <integer value="0" />
-                <float value="0.5" />
+                <real value="0.5" />
             </arguments>
         </call>
         <each variable="v">
diff --git a/src/instruction.rs b/src/instruction.rs
index 43fe269..f170654 100644
--- a/src/instruction.rs
+++ b/src/instruction.rs
@@ -14,8 +14,8 @@ pub enum Instruction {
     Assign(String, Box<Instruction>),
     Integer(String),
     IntegerCast(Box<Instruction>),
-    Float(String),
-    FloatCast(Box<Instruction>),
+    Real(String),
+    RealCast(Box<Instruction>),
     String(String),
     StringCast(Box<Instruction>),
     Array(Vec<Instruction>),
@@ -73,13 +73,13 @@ impl Instruction {
                     Err(MissingAttribute("integer", "value"))?
                 }
             }
-            "float" => {
+            "real" => {
                 if let Some(v) = node.attribute("value") {
-                    Instruction::Float(String::from(v))
+                    Instruction::Real(String::from(v))
                 } else if let Some(n) = node.first_element_child() {
-                    Instruction::FloatCast(Box::new(Instruction::new(n)?))
+                    Instruction::RealCast(Box::new(Instruction::new(n)?))
                 } else {
-                    Err(MissingAttribute("float", "value"))?
+                    Err(MissingAttribute("real", "value"))?
                 }
             }
             "string" => {
@@ -270,14 +270,14 @@ impl Instruction {
             ))
         } else if vals
             .iter()
-            .all(|v| matches!(v, Value::Integer(_)) || matches!(v, Value::Float(_)))
+            .all(|v| matches!(v, Value::Integer(_)) || matches!(v, Value::Real(_)))
         {
-            Ok(Value::Float(
+            Ok(Value::Real(
                 vals.iter()
                     .map(|v| {
                         if let Value::Integer(i) = v {
                             Ok(*i as f64)
-                        } else if let Value::Float(f) = v {
+                        } else if let Value::Real(f) = v {
                             Ok(*f)
                         } else {
                             Err(InvalidValue("add"))?
@@ -287,7 +287,7 @@ impl Instruction {
             ))
         } else if vals.iter().all(|v| {
             matches!(v, Value::Integer(_))
-                || matches!(v, Value::Float(_))
+                || matches!(v, Value::Real(_))
                 || matches!(v, Value::String(_))
         }) {
             Ok(Value::String(
@@ -297,7 +297,7 @@ impl Instruction {
                             s.to_string()
                         } else if let Value::Integer(i) = v {
                             i.to_string()
-                        } else if let Value::Float(f) = v {
+                        } else if let Value::Real(f) = v {
                             f.to_string()
                         } else {
                             Err(InvalidValue("add"))?
@@ -333,14 +333,14 @@ impl Instruction {
             )
         } else if vals
             .iter()
-            .all(|v| matches!(v, Value::Integer(_)) || matches!(v, Value::Float(_)))
+            .all(|v| matches!(v, Value::Integer(_)) || matches!(v, Value::Real(_)))
         {
             let first = match vals.first().ok_or(BadChildCount("subtract", 0usize))? {
                 Value::Integer(v) => *v as f64,
-                Value::Float(v) => *v,
+                Value::Real(v) => *v,
                 _ => Err(InvalidValue("subtract"))?,
             };
-            Value::Float(
+            Value::Real(
                 first
                     - vals
                         .iter()
@@ -348,7 +348,7 @@ impl Instruction {
                         .map(|val| {
                             Ok(match val {
                                 Value::Integer(v) => *v as f64,
-                                Value::Float(v) => *v,
+                                Value::Real(v) => *v,
                                 _ => Err(InvalidValue("subtract"))?,
                             })
                         })
@@ -374,14 +374,14 @@ impl Instruction {
             ))
         } else if vals
             .iter()
-            .all(|v| matches!(v, Value::Integer(_)) || matches!(v, Value::Float(_)))
+            .all(|v| matches!(v, Value::Integer(_)) || matches!(v, Value::Real(_)))
         {
-            Ok(Value::Float(
+            Ok(Value::Real(
                 vals.iter()
                     .map(|val| {
                         Ok(match val {
                             Value::Integer(v) => *v as f64,
-                            Value::Float(v) => *v,
+                            Value::Real(v) => *v,
                             _ => Err(InvalidValue("multiply"))?,
                         })
                     })
@@ -395,14 +395,14 @@ impl Instruction {
     fn divide(vals: Vec<Value>) -> Result<Value, Box<dyn Error>> {
         if vals
             .iter()
-            .all(|v| matches!(v, Value::Integer(_)) || matches!(v, Value::Float(_)))
+            .all(|v| matches!(v, Value::Integer(_)) || matches!(v, Value::Real(_)))
         {
             let first = match vals.first().ok_or(BadChildCount("divide", 0))? {
                 Value::Integer(v) => *v as f64,
-                Value::Float(v) => *v,
+                Value::Real(v) => *v,
                 _ => Err(InvalidValue("divide"))?,
             };
-            Ok(Value::Float(
+            Ok(Value::Real(
                 first
                     * vals
                         .iter()
@@ -410,7 +410,7 @@ impl Instruction {
                         .map(|val| {
                             Ok(match val {
                                 Value::Integer(v) => 1.0 / (*v as f64),
-                                Value::Float(v) => 1.0 / *v,
+                                Value::Real(v) => 1.0 / *v,
                                 _ => Err(InvalidValue("divide"))?,
                             })
                         })
@@ -442,7 +442,7 @@ impl Instruction {
         match v1 {
             Value::Integer(i1) => match v2 {
                 Value::Integer(i2) => Ok(i1 - i2),
-                Value::Float(f2) => Ok(
+                Value::Real(f2) => Ok(
                     match (i1 as f64).partial_cmp(&f2).ok_or(IncompatibleValues)? {
                         Ordering::Less => -1,
                         Ordering::Equal => 0,
@@ -451,7 +451,7 @@ impl Instruction {
                 ),
                 _ => Err(IncompatibleValues)?,
             },
-            Value::Float(f1) => match v2 {
+            Value::Real(f1) => match v2 {
                 Value::Integer(i2) => Ok(
                     match f1.partial_cmp(&(i2 as f64)).ok_or(IncompatibleValues)? {
                         Ordering::Less => -1,
@@ -459,7 +459,7 @@ impl Instruction {
                         Ordering::Greater => 1,
                     },
                 ),
-                Value::Float(f2) => Ok(match f1.partial_cmp(&f2).ok_or(IncompatibleValues)? {
+                Value::Real(f2) => Ok(match f1.partial_cmp(&f2).ok_or(IncompatibleValues)? {
                     Ordering::Less => -1,
                     Ordering::Equal => 0,
                     Ordering::Greater => 1,
@@ -511,25 +511,25 @@ impl Instruction {
                 Instruction::IntegerCast(ins) => Some(Value::Integer(
                     match ins.run(ctx, globals)?.ok_or(InvalidValue("integer"))? {
                         Value::Integer(i) => i,
-                        Value::Float(f) => f as i64,
+                        Value::Real(f) => f as i64,
                         Value::String(s) => s.parse()?,
                         _ => Err(InvalidValue("integer"))?,
                     },
                 )),
-                Instruction::Float(val) => Some(Value::Float(val.parse()?)),
-                Instruction::FloatCast(ins) => Some(Value::Float(
-                    match ins.run(ctx, globals)?.ok_or(InvalidValue("float"))? {
+                Instruction::Real(val) => Some(Value::Real(val.parse()?)),
+                Instruction::RealCast(ins) => Some(Value::Real(
+                    match ins.run(ctx, globals)?.ok_or(InvalidValue("real"))? {
                         Value::Integer(i) => i as f64,
-                        Value::Float(f) => f,
+                        Value::Real(f) => f,
                         Value::String(s) => s.parse()?,
-                        _ => Err(InvalidValue("float"))?,
+                        _ => Err(InvalidValue("real"))?,
                     },
                 )),
                 Instruction::String(val) => Some(Value::String(val.clone())),
                 Instruction::StringCast(ins) => Some(Value::String(
                     match ins.run(ctx, globals)?.ok_or(InvalidValue("string"))? {
                         Value::Integer(i) => i.to_string(),
-                        Value::Float(f) => f.to_string(),
+                        Value::Real(f) => f.to_string(),
                         Value::String(s) => s,
                         _ => Err(InvalidValue("string"))?,
                     },
diff --git a/src/stl.rs b/src/stl.rs
index 8dec93b..a49faef 100644
--- a/src/stl.rs
+++ b/src/stl.rs
@@ -35,7 +35,7 @@ fn print(vals: Vec<Value>) -> Result<Option<Value>, Box<dyn Error>> {
     if vals.len() == 1 {
         match &vals[0] {
             Value::Integer(i) => print!("{}", i),
-            Value::Float(f) => print!("{}", f),
+            Value::Real(f) => print!("{}", f),
             Value::String(s) => print!("{}", s),
             v => print!("{:?}", v), // _ => Err("unprintable value")?,
         };
@@ -50,7 +50,7 @@ fn print_line(vals: Vec<Value>) -> Result<Option<Value>, Box<dyn Error>> {
     if vals.len() == 1 {
         match &vals[0] {
             Value::Integer(i) => println!("{}", i),
-            Value::Float(f) => println!("{}", f),
+            Value::Real(f) => println!("{}", f),
             Value::String(s) => println!("{}", s),
             v => println!("{:?}", v), // _ => Err("unprintable value")?,
         };
diff --git a/src/value.rs b/src/value.rs
index de6f563..2f477e1 100644
--- a/src/value.rs
+++ b/src/value.rs
@@ -50,7 +50,7 @@ impl Function {
 #[derive(Clone, Debug)]
 pub enum Value {
     Integer(i64),
-    Float(f64),
+    Real(f64),
     String(String),
     Array(Rc<RefCell<Vec<Value>>>),
     Function(Function),
@@ -61,7 +61,7 @@ impl Value {
     pub fn to_bool(&self) -> bool {
         match self {
             Value::Integer(i) => *i != 0,
-            Value::Float(f) => *f != 0.0,
+            Value::Real(f) => *f != 0.0,
             Value::String(s) => s.len() != 0,
             Value::Array(v) => v.borrow().len() != 0,
             _ => true,