PRACTICE: PRESENT PERFECT

https://docs.google.com/presentation/d/17e4oPF3xV5K98wskfVzJPnsnh0KrIGlw/edit?usp=sharing&ouid=110148714800773127676&rtpof=true&sd=true

1. We have constructed this entire model based on data types.
2. In the 1970s, Kay's Smalltalk work had influenced the Lisp community to incorporate object-based techniques.
3. Object-oriented features have been added to many existing languages during that time, including Ada, BASIC, Fortran, Pascal, and others.
4. More recently, a number of languages have emerged that are primarily object-oriented yet compatible with procedural methodology.
5. Languages that are historically procedural languages have been extended with some OO features.
6. A tag contains the index of the datum in main memory that has been in the cache.